Adhesive compositions and methods

ABSTRACT

The present invention encompasses polyurethane adhesive compositions comprising aliphatic polycarbonate chains. In one aspect, the present invention encompasses polyurethane adhesives derived from aliphatic polycarbonate polyols and polyisocyanates wherein the polyol chains contain a primary repeating unit having a structure: 
     
       
         
         
             
             
         
       
     
     In another aspect, the invention provides articles comprising the inventive polyurethane compositions as well as methods of making such compositions.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application claims priority to U.S. provisional patent application Nos. 61/625,065, filed Apr. 16, 2012, and 61/683,277, filed Aug. 15, 2012, the entirety of each of which is hereby incorporated by reference.

GOVERNMENT SUPPORT

The invention was made in part with United States Government support under grants DE-FE0002474 awarded by the Department of Energy. The United States Government has certain rights in the invention.

FIELD OF THE INVENTION

This invention pertains to the field of polymers. More particularly, the invention pertains to polyurethane adhesives incorporating aliphatic polycarbonate polyols obtained via copolymerization of epoxides and carbon dioxide. Polyurethane adhesives are used for creating adhesive films as well as joining two substrates to one another.

BACKGROUND OF THE INVENTION

Polyurethanes adhesives are a unique urethanes product group that vary widely in composition and are used in many different applications and market segments. Typical product forms include reactive types such as 1-component, 2-component and hot-melt compositions, as well as non-reactive types such as solvent-borne, water-borne and hot-melt compositions, among others.

Polyurethane adhesives are normally defined as those adhesives that contain a number of urethane groups in the molecular backbone of a polymer comprising the adhesive or which are formed during use, regardless of the chemical composition of the rest of the chain. Thus a typical urethane adhesive may contain, in addition to urethane linkages, aliphatic and aromatic hydrocarbons, esters, ethers, amides, urea and allophonate groups. An isocyanate group reacts with the hydroxyl groups of a polyol to form the repeating urethane linkage. Isocyanates will react with water to form a urea linkage and carbon dioxide as a by-product. Linear polyurethane adhesives may be obtained by using compounds with two reactive groups such as diisocyanates and diols. When polyols with three or more hydroxyl groups (i.e. a functionality of 3 or more) are reacted with an polyisocyanate, or when isocyanates with three or more isocyanate groups are reacted with a polyol the resulting polymer is crosslinked. In reaction systems where there is an excess of isocyanate, crosslinking reactions may occur. Often, excess isocyante in the composition reacts with atmospheric water or moisture contained in the substrate.

One component adhesives are usually viscous liquid isocyanate-terminated pre-polymers at room temperature. They set by reaction of the free isocyantes groups with atmospheric moisture or with moisture contained in the substrate to form poly urea groups. They typically do not require mixing with other components before curing. The prepolymers are prepared by reacting an excess of isocyanate with polyols. If the functionality of the prepolymer is greater than two the cured film will be chemically crosslinked.

Two component polyurethane adhesive compositions generally comprise components that are liquids or pastes at room temperature before they are mixed together. The first component of the composition comprises a polyol and other ingredients, such as chain extenders, catalysts, blocking agents and other additives as desired. The second component comprises monomeric, polymeric or prepolymeric polyisocyanate. In order to make a bond, the two components of the adhesive are fully mixed together and the composition is then applied to a substrate. The mixed composition then initiates cure and develops bonding strength while transforming into a solid form. The curing reaction takes place between the free isocyanate groups and the active hydrogens from the polyol. If there are excess free isocyanate groups after the main curing reaction, the excess free isocyanate groups are cured by ambient or surface moisture from the substrates. The isocyanates and polyols employed may have a functionality of two or higher to provide crosslinking in the adhesive.

Reactive hot melt adhesives are characterized as a readily meltable polyisocyanate polyurethane (NCO prepolymer) which is usually solid or highly viscous at room temperature. They set both physically by cooling and chemically by reaction with atmospheric moisture. Depending on the formulation, reactive polyurethane hot-melt adhesives cure to form elastomsers with flexible to hard properties and tough adhesive layers. The prepolymers typically have a low free isocyanate content.

Non reactive solvent borne and water borne adhesives typically consist of a hydroxyl terminated polyurethane dissolved in a solvent. The polyurethanes are usually obtained by reacting a diol with a diisocyante. The polymer solutions are applied to both substrate surfaces to be bonded, some time is allowed for the solvents to evaporate and the surfaces are bonded together, at which point interdiffusions of the polymer chains will occur.

Non-reactive hot melt adhesives typically consist of linear chains that are solid at room temperature and are often used in the lamination of textiles although they have many other applications. They usually consist of hydroxyl-terminated polyurethanes that form the adhesive bond by cooling from the molten state. In some cases these are also known as thermoplastic polyurethane adhesives.

SUMMARY OF THE INVENTION

In one aspect, the present invention encompasses polyurethane adhesives comprising polyisocyanates and aliphatic polycarbonate polyols derived from the copolymerization of CO₂ with one or more epoxides. In one aspect, the aliphatic polycarbonate polyol chains contain a primary repeating unit having a structure:

-   -   where R¹, R², R³, and R⁴ are, at each occurrence in the polymer         chain, independently selected from the group consisting of —H,         fluorine, an optionally substituted C₁₋₄₀ aliphatic group, an         optionally substituted C₁₋₂₀ heteroaliphatic group, and an         optionally substituted aryl group, where any two or more of R¹,         R², R³, and R⁴ may optionally be taken together with intervening         atoms to form one or more optionally substituted rings         optionally containing one or more heteroatoms.

In certain embodiments, such aliphatic polycarbonate chains are derived from the copolymerization of carbon dioxide with one or more epoxide substrates. Such copolymerizations are exemplified in published PCT application WO 2010/028362, the entirety of which is incorporated herein by reference. In some embodiments, the aliphatic polycarbonate chains are derived from ethylene oxide, propylene oxide, or optionally substituted C₃₋₃₀ aliphatic epoxides, or mixtures of two or more of these. In some embodiments, the aliphatic polycarbonate chains have a number average molecular weight (Mn) less than about 20,000 g/mol. In certain embodiments, the aliphatic polycarbonate polyols have a functional number of between about 1.8 and about 6.

In another aspect, the present invention encompasses isocyanate-terminated prepolymers comprising a plurality of epoxide-CO₂-derived polyol segments linked via urethane bonds formed from reaction with polyisocyanate compounds.

In another embodiment, the invention comprises a process for bonding two substrates together by contacting the adhesive composition of the invention with at least one of the substrates and contacting the substrates together along a portion to which the adhesive was applied, and allowing the adhesive to cure thereby bonding the substrates together.

DEFINITIONS

Definitions of specific functional groups and chemical terms are described in more detail below. For purposes of this invention, the chemical elements are identified in accordance with the Periodic Table of the Elements, CAS version, Handbook of Chemistry and Physics, 75^(th) Ed., inside cover, and specific functional groups are generally defined as described therein. Additionally, general principles of organic chemistry, as well as specific functional moieties and reactivity, are described in Organic Chemistry, Thomas Sorrell, University Science Books, Sausalito, 1999; Smith and March March's Advanced Organic Chemistry, 5^(th) Edition, John Wiley & Sons, Inc., New York, 2001; Larock, Comprehensive Organic Transformations, VCH Publishers, Inc., New York, 1989; Carruthers, Some Modern Methods of Organic Synthesis, 3^(rd) Edition, Cambridge University Press, Cambridge, 1987; the entire contents of each of which are incorporated herein by reference.

Certain compounds of the present invention can comprise one or more asymmetric centers, and thus can exist in various stereoisomeric forms, e.g., enantiomers and/or diastereomers. Thus, inventive compounds and compositions thereof may be in the form of an individual enantiomer, diastereomer or geometric isomer, or may be in the form of a mixture of stereoisomers. In certain embodiments, the compounds of the invention are enantiopure compounds. In certain embodiments, mixtures of enantiomers or diastereomers are provided.

Furthermore, certain compounds, as described herein may have one or more double bonds that can exist as either the Z or E isomer, unless otherwise indicated. The invention additionally encompasses the compounds as individual isomers substantially free of other isomers and alternatively, as mixtures of various isomers, e.g., racemic mixtures of enantiomers. In addition to the above-mentioned compounds per se, this invention also encompasses compositions comprising one or more compounds.

As used herein, the term “isomers” includes any and all geometric isomers and stereoisomers. For example, “isomers” include cis- and trans-isomers, E- and Z-isomers, R- and S-enantiomers, diastereomers, (D)-isomers, (L)-isomers, racemic mixtures thereof, and other mixtures thereof, as falling within the scope of the invention. For instance, a stereoisomer may, in some embodiments, be provided substantially free of one or more corresponding stereoisomers, and may also be referred to as “stereochemically enriched.”

Where a particular enantiomer is preferred, it may, in some embodiments be provided substantially free of the opposite enantiomer, and may also be referred to as “optically enriched.” “Optically enriched,” as used herein, means that the compound or polymer is made up of a significantly greater proportion of one enantiomer. In certain embodiments the compound is made up of at least about 90% by weight of a preferred enantiomer. In other embodiments the compound is made up of at least about 95%, 98%, or 99% by weight of a preferred enantiomer. Preferred enantiomers may be isolated from racemic mixtures by any method known to those skilled in the art, including chiral high pressure liquid chromatography (HPLC) and the formation and crystallization of chiral salts or prepared by asymmetric syntheses. See, for example, Jacques, et al., Enantiomers, Racemates and Resolutions (Wiley Interscience, New York, 1981); Wilen, S. H., et al., Tetrahedron 33:2725 (1977); Eliel, E. L. Stereochemistry of Carbon Compounds (McGraw-Hill, NY, 1962); Wilen, S. H. Tables of Resolving Agents and Optical Resolutions p. 268 (E. L. Eliel, Ed., Univ. of Notre Dame Press, Notre Dame, Ind. 1972).

The term “epoxide”, as used herein, refers to a substituted or unsubstituted oxirane. Such substituted oxiranes include monosubstituted oxiranes, disubstituted oxiranes, trisubstituted oxiranes, and tetrasubstituted oxiranes. Such epoxides may be further optionally substituted as defined herein. In certain embodiments, epoxides comprise a single oxirane moiety. In certain embodiments, epoxides comprise two or more oxirane moieties.

The term “polymer”, as used herein, refers to a molecule of high relative molecular mass, the structure of which comprises the multiple repetition of units derived, actually or conceptually, from molecules of low relative molecular mass. In certain embodiments, a polymer is comprised of substantially alternating units derived from CO₂ and an epoxide (e.g., poly(ethylene carbonate). In certain embodiments, a polymer of the present invention is a copolymer, terpolymer, heteropolymer, block copolymer, or tapered heteropolymer incorporating two or more different epoxide monomers. With respect to the structural depiction of such higher polymers, the convention of showing enchainment of different monomer units separated by a slash may be used herein

These structures are to be interpreted to encompass copolymers incorporating any ratio of the different monomer units depicted unless otherwise specified. This depiction is also meant to represent random, tapered, block co-polymers, and combinations of any two or more of these and all of these are implied unless otherwise specified.

The terms “halo” and “halogen” as used herein refer to an atom selected from fluorine (fluoro, —F), chlorine (chloro, —Cl), bromine (bromo, —Br), and iodine (iodo, —I).

The term “aliphatic” or “aliphatic group”, as used herein, denotes a hydrocarbon moiety that may be straight-chain (i.e., unbranched), branched, or cyclic (including fused, bridging, and spiro-fused polycyclic) and may be completely saturated or may contain one or more units of unsaturation, but which is not aromatic. Unless otherwise specified, aliphatic groups contain 1-40 carbon atoms. In certain embodiments, aliphatic groups contain 1-20 carbon atoms. In certain embodiments, aliphatic groups contain 3-20 carbon atoms. In certain embodiments, aliphatic groups contain 1-12 carbon atoms. In certain embodiments, aliphatic groups contain 1-8 carbon atoms. In certain embodiments, aliphatic groups contain 1-6 carbon atoms. In some embodiments, aliphatic groups contain 1-5 carbon atoms, in some embodiments, aliphatic groups contain 1-4 carbon atoms, in some embodiments aliphatic groups contain 1-3 carbon atoms, and in some embodiments aliphatic groups contain 1 or 2 carbon atoms. Suitable aliphatic groups include, but are not limited to, linear or branched, alkyl, alkenyl, and alkynyl groups, and hybrids thereof such as (cycloalkyl)alkyl, (cycloalkenyl)alkyl or (cycloalkyl)alkenyl.

The term “heteroaliphatic,” as used herein, refers to aliphatic groups wherein one or more carbon atoms are independently replaced by one or more atoms selected from the group consisting of oxygen, sulfur, nitrogen, or phosphorus. In certain embodiments, one to six carbon atoms are independently replaced by one or more of oxygen, sulfur, nitrogen, or phosphorus. Heteroaliphatic groups may be substituted or unsubstituted, branched or unbranched, cyclic or acyclic, and include saturated, unsaturated or partially unsaturated groups.

As used herein, the term “bivalent C₁₋₈ (or C₁₋₃) saturated or unsaturated, straight or branched, hydrocarbon chain”, refers to bivalent alkyl, alkenyl, and alkynyl, chains that are straight or branched as defined herein.

The term “unsaturated”, as used herein, means that a moiety has one or more double or triple bonds.

The terms “cycloaliphatic”, “carbocycle”, or “carbocyclic”, used alone or as part of a larger moiety, refer to a saturated or partially unsaturated cyclic aliphatic monocyclic or polycyclic ring systems, as described herein, having from 3 to 12 members, wherein the aliphatic ring system is optionally substituted as defined above and described herein. Cycloaliphatic groups include, without limitation, cyclopropyl, cyclobutyl, cyclopentyl, cyclopentenyl, cyclohexyl, cyclohexenyl, cycloheptyl, cycloheptenyl, cyclooctyl, cyclooctenyl, norbornyl, adamantyl, and cyclooctadienyl. In some embodiments, the cycloalkyl has 3-6 carbons. The terms “cycloaliphatic”, “carbocycle” or “carbocyclic” also include aliphatic rings that are fused to one or more aromatic or nonaromatic rings, such as decahydronaphthyl or tetrahydronaphthyl, where the radical or point of attachment is on the aliphatic ring. In certain embodiments, the term “3- to 7-membered carbocycle” refers to a 3- to 7-membered saturated or partially unsaturated monocyclic carbocyclic ring. In certain embodiments, the term “3- to 8-membered carbocycle” refers to a 3- to 8-membered saturated or partially unsaturated monocyclic carbocyclic ring. In certain embodiments, the terms “3- to 14-membered carbocycle” and “C₃₋₁₄ carbocycle” refer to a 3- to 8-membered saturated or partially unsaturated monocyclic carbocyclic ring, or a 7- to 14-membered saturated or partially unsaturated polycyclic carbocyclic ring.

The term “alkyl,” as used herein, refers to saturated, straight- or branched-chain hydrocarbon radicals derived from an aliphatic moiety containing between one and six carbon atoms by removal of a single hydrogen atom. Unless otherwise specified, alkyl groups contain 1-12 carbon atoms. In certain embodiments, alkyl groups contain 1-8 carbon atoms. In certain embodiments, alkyl groups contain 1-6 carbon atoms. In some embodiments, alkyl groups contain 1-5 carbon atoms, in some embodiments, alkyl groups contain 1-4 carbon atoms, in some embodiments alkyl groups contain 1-3 carbon atoms, and in some embodiments alkyl groups contain 1-2 carbon atoms. Examples of alkyl radicals include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, iso-butyl, sec-butyl, sec-pentyl, iso-pentyl, tert-butyl, n-pentyl, neopentyl, n-hexyl, sec-hexyl, n-heptyl, n-octyl, n-decyl, n-undecyl, dodecyl, and the like.

The term “alkenyl,” as used herein, denotes a monovalent group derived from a straight- or branched-chain aliphatic moiety having at least one carbon-carbon double bond by the removal of a single hydrogen atom. Unless otherwise specified, alkenyl groups contain 2-12 carbon atoms. In certain embodiments, alkenyl groups contain 2-8 carbon atoms. In certain embodiments, alkenyl groups contain 2-6 carbon atoms. In some embodiments, alkenyl groups contain 2-5 carbon atoms, in some embodiments, alkenyl groups contain 2-4 carbon atoms, in some embodiments alkenyl groups contain 2-3 carbon atoms, and in some embodiments alkenyl groups contain 2 carbon atoms. Alkenyl groups include, for example, ethenyl, propenyl, butenyl, 1-methyl-2-buten-1-yl, and the like.

The term “alkynyl,” as used herein, refers to a monovalent group derived from a straight- or branched-chain aliphatic moiety having at least one carbon-carbon triple bond by the removal of a single hydrogen atom. Unless otherwise specified, alkynyl groups contain 2-12 carbon atoms. In certain embodiments, alkynyl groups contain 2-8 carbon atoms. In certain embodiments, alkynyl groups contain 2-6 carbon atoms. In some embodiments, alkynyl groups contain 2-5 carbon atoms, in some embodiments, alkynyl groups contain 2-4 carbon atoms, in some embodiments alkynyl groups contain 2-3 carbon atoms, and in some embodiments alkynyl groups contain 2 carbon atoms. Representative alkynyl groups include, but are not limited to, ethynyl, 2-propynyl (propargyl), 1-propynyl, and the like.

The term “alkoxy”, as used herein refers to an alkyl group, as previously defined, attached to the parent molecule through an oxygen atom. Examples of alkoxy, include but are not limited to, methoxy, ethoxy, propoxy, isopropoxy, n-butoxy, tert-butoxy, neopentoxy, and n-hexoxy.

The term “acyl”, as used herein, refers to a carbonyl-containing functionality, e.g., —C(═O)R, wherein R is hydrogen or an optionally substituted aliphatic, heteroaliphatic, heterocyclic, aryl, heteroaryl group, or is a substituted (e.g., with hydrogen or aliphatic, heteroaliphatic, aryl, or heteroaryl moieties) oxygen or nitrogen containing functionality (e.g., forming a carboxylic acid, ester, or amide functionality). The term “acyloxy”, as used here, refers to an acyl group attached to the parent molecule through an oxygen atom.

The term “aryl” used alone or as part of a larger moiety as in “aralkyl”, “aralkoxy”, or “aryloxyalkyl”, refers to monocyclic and polycyclic ring systems having a total of five to 20 ring members, wherein at least one ring in the system is aromatic and wherein each ring in the system contains three to twelve ring members. The term “aryl” may be used interchangeably with the term “aryl ring”. In certain embodiments of the present invention, “aryl” refers to an aromatic ring system which includes, but is not limited to, phenyl, biphenyl, naphthyl, anthracyl and the like, which may bear one or more substituents. Also included within the scope of the term “aryl”, as it is used herein, is a group in which an aromatic ring is fused to one or more additional rings, such as benzofuranyl, indanyl, phthalimidyl, naphthimidyl, phenantriidinyl, or tetrahydronaphthyl, and the like. In certain embodiments, the terms “6- to 10-membered aryl” and “C₆₋₁₀ aryl” refer to a phenyl or an 8- to 10-membered polycyclic aryl ring.

The terms “heteroaryl” and “heteroar-”, used alone or as part of a larger moiety, e.g., “heteroaralkyl”, or “heteroaralkoxy”, refer to groups having 5 to 14 ring atoms, preferably 5, 6, or 9 ring atoms; having 6, 10, or 14 it electrons shared in a cyclic array; and having, in addition to carbon atoms, from one to five heteroatoms. The term “heteroatom” refers to nitrogen, oxygen, or sulfur, and includes any oxidized form of nitrogen or sulfur, and any quaternized form of a basic nitrogen. Heteroaryl groups include, without limitation, thienyl, furanyl, pyrrolyl, imidazolyl, pyrazolyl, triazolyl, tetrazolyl, oxazolyl, isoxazolyl, oxadiazolyl, thiazolyl, isothiazolyl, thiadiazolyl, pyridyl, pyridazinyl, pyrimidinyl, pyrazinyl, indolizinyl, purinyl, naphthyridinyl, benzofuranyl and pteridinyl. The terms “heteroaryl” and “heteroar-”, as used herein, also include groups in which a heteroaromatic ring is fused to one or more aryl, cycloaliphatic, or heterocyclyl rings, where the radical or point of attachment is on the heteroaromatic ring. Nonlimiting examples include indolyl, isoindolyl, benzothienyl, benzofuranyl, dibenzofuranyl, indazolyl, benzimidazolyl, benzthiazolyl, quinolyl, isoquinolyl, cinnolinyl, phthalazinyl, quinazolinyl, quinoxalinyl, 4H-quinolizinyl, carbazolyl, acridinyl, phenazinyl, phenothiazinyl, phenoxazinyl, tetrahydroquinolinyl, tetrahydroisoquinolinyl, and pyrido[2,3-b]-1,4-oxazin-3(4H)-one. A heteroaryl group may be mono- or bicyclic. The term “heteroaryl” may be used interchangeably with the terms “heteroaryl ring”, “heteroaryl group”, or “heteroaromatic”, any of which terms include rings that are optionally substituted. The term “heteroaralkyl” refers to an alkyl group substituted by a heteroaryl, wherein the alkyl and heteroaryl portions independently are optionally substituted. In certain embodiments, the term “5- to 10-membered heteroaryl” refers to a 5- to 6-membered heteroaryl ring having 1 to 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or an 8- to 10-membered bicyclic heteroaryl ring having 1 to 4 heteroatoms independently selected from nitrogen, oxygen, or sulfur. In certain embodiments, the term “5- to 12-membered heteroaryl” refers to a 5- to 6-membered heteroaryl ring having 1 to 3 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or an 8- to 12-membered bicyclic heteroaryl ring having 1 to 4 heteroatoms independently selected from nitrogen, oxygen, or sulfur.

As used herein, the terms “heterocycle”, “heterocyclyl”, “heterocyclic radical”, and “heterocyclic ring” are used interchangeably and refer to a stable 5- to 7-membered monocyclic or 7-14-membered polycyclic heterocyclic moiety that is either saturated or partially unsaturated, and having, in addition to carbon atoms, one or more, preferably one to four, heteroatoms, as defined above. When used in reference to a ring atom of a heterocycle, the term “nitrogen” includes a substituted nitrogen. As an example, in a saturated or partially unsaturated ring having 0-3 heteroatoms selected from oxygen, sulfur or nitrogen, the nitrogen may be N (as in 3,4-dihydro-2H-pyrrolyl), NH (as in pyrrolidinyl), or ⁺NR (as in N-substituted pyrrolidinyl). In some embodiments, the term “3- to 7-membered heterocyclic” refers to a 3- to 7-membered saturated or partially unsaturated monocyclic heterocyclic ring having 1 to 2 heteroatoms independently selected from nitrogen, oxygen, or sulfur. In some embodiments, the term “3- to 12-membered heterocyclic” refers to a 3- to 8-membered saturated or partially unsaturated monocyclic heterocyclic ring having 1 to 2 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or a 7- to 12-membered saturated or partially unsaturated polycyclic heterocyclic ring having 1-3 heteroatoms independently selected from nitrogen, oxygen, or sulfur.

A heterocyclic ring can be attached to its pendant group at any heteroatom or carbon atom that results in a stable structure and any of the ring atoms can be optionally substituted. Examples of such saturated or partially unsaturated heterocyclic radicals include, without limitation, tetrahydrofuranyl, tetrahydrothienyl, pyrrolidinyl, pyrrolidonyl, piperidinyl, pyrrolinyl, tetrahydroquinolinyl, tetrahydroisoquinolinyl, decahydroquinolinyl, oxazolidinyl, piperazinyl, dioxanyl, dioxolanyl, diazepinyl, oxazepinyl, thiazepinyl, morpholinyl, and quinuclidinyl. The terms “heterocycle”, “heterocyclyl”, “heterocyclyl ring”, “heterocyclic group”, “heterocyclic moiety”, and “heterocyclic radical”, are used interchangeably herein, and also include groups in which a heterocyclyl ring is fused to one or more aryl, heteroaryl, or cycloaliphatic rings, such as indolinyl, 3H-indolyl, chromanyl, phenanthridinyl, or tetrahydroquinolinyl, where the radical or point of attachment is on the heterocyclyl ring. A heterocyclyl group may be mono- or bicyclic. The term “heterocyclylalkyl” refers to an alkyl group substituted by a heterocyclyl, wherein the alkyl and heterocyclyl portions independently are optionally substituted.

As used herein, the term “partially unsaturated” refers to a ring moiety that includes at least one double or triple bond. The term “partially unsaturated” is intended to encompass rings having multiple sites of unsaturation, but is not intended to include aryl or heteroaryl moieties, as herein defined.

As described herein, compounds of the invention may contain “optionally substituted” moieties. In general, the term “substituted”, whether preceded by the term “optionally” or not, means that one or more hydrogens of the designated moiety are replaced with a suitable substituent. Unless otherwise indicated, an “optionally substituted” group may have a suitable substituent at each substitutable position of the group, and when more than one position in any given structure may be substituted with more than one substituent selected from a specified group, the substituent may be either the same or different at every position. Combinations of substituents envisioned by this invention are preferably those that result in the formation of stable or chemically feasible compounds. The term “stable”, as used herein, refers to compounds that are not substantially altered when subjected to conditions to allow for their production, detection, and, in certain embodiments, their recovery, purification, and use for one or more of the purposes disclosed herein.

Suitable monovalent substituents on a substitutable carbon atom of an “optionally substituted” group are independently halogen; —(CH₂)₀₋₄R^(∘); —(CH₂)₀₋₄OR^(∘); —O—(CH₂)₀₋₄C(O)OR^(∘); —(CH₂)₀₋₄CH(OR^(∘))₂; —(CH₂)₀₋₄SR^(∘); —(CH₂)₀₋₄Ph, which may be substituted with R^(∘); —(CH₂)₀₋₄O(CH₂)₀₋₁Ph which may be substituted with R^(∘); —CH═CHPh, which may be substituted with R^(∘); NO₂; —CN; —N₃; —(CH₂)₀₋₄N(R^(∘))₂; —(CH₂)₀₋₄N(R^(∘)C(O)R^(∘); —N(R^(∘))C(S)R^(∘); —(CH₂)₀₋₄N(R^(∘)C(O)N(R^(∘))₂; —N(R^(∘)C(S)N(R^(∘))₂; —(CH₂)₀₋₄N(R^(∘)C(O)OR^(∘); —N(R^(∘))N(R^(∘))C(O)R^(∘); —N(R^(∘)N(R^(∘)C(O)N(R^(∘))₂; —N(R^(∘)N(R^(∘)C(O)OR^(∘); —(CH₂)₀₋₄C(O)R^(∘); —C(S)R^(∘); —(CH₂)₀₋₄C(O)OR^(∘); —(CH₂)₀₋₄C(O)N(R^(∘))₂; —(CH₂)₀₋₄C(O)SR^(∘); —(CH₂)₀₋₄C(O)OSiR^(∘) ₃; —(CH₂)₀₋₄OC(O)R^(∘); —OC(O)(CH₂)₀₋₄SR—, SC(S)SR^(∘); —(CH₂)₀₋₄SC(O)R^(∘); —(CH₂)₀₋₄C(O)NR^(∘))₂; —C(S)NR^(∘))₂; —C(S)SR^(∘); —SC(S)SR^(∘), —(CH₂)₀₋₄OC(O)NR^(∘))₂; α C(O)N(OR^(∘)R^(∘); —C(O)C(O)R^(∘); —C(O)CH₂C(O)R^(∘); —C(NOR^(∘)R^(∘); —(CH₂)₀₋₄SSR^(∘); —(CH₂)₀₋₄S(O)₂R^(∘); —(CH₂)₀₋₄S(O)₂OR^(∘); —(CH₂)₀₋₄OS(O)₂R^(∘); —S(O)₂NR^(∘))₂; —(CH₂)₀₋₄S(O)R^(∘); —N(R^(∘)S(O)₂NR^(∘))₂; —N(R^(∘)S(O)₂R^(∘); —N(OR^(∘)R^(∘); —C(NH)NR^(∘))₂; —P(O)₂R^(∘); —P(O)R^(∘))₂; —OP(O)R^(∘))₂; —OP(O)(OR^(∘))₂; SiR^(∘) ₃; —(C₁₋₄ straight or branched)alkylene)O—N(R^(∘))₂; or —(C₁₋₄ straight or branched)alkylene)C(O)O—N(R^(∘))₂, wherein each R^(∘) may be substituted as defined below and is independently hydrogen, C₁₋₈ aliphatic, —CH₂Ph, —O(CH₂)₀₋₁Ph, or a 5-6-membered saturated, partially unsaturated, or aryl ring having 0-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or, notwithstanding the definition above, two independent occurrences of R^(∘), taken together with their intervening atom(s), form a 3-12-membered saturated, partially unsaturated, or aryl mono- or polycyclic ring having 0-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, which may be substituted as defined below.

Suitable monovalent substituents on R^(∘) (or the ring formed by taking two independent occurrences of R^(∘) together with their intervening atoms), are independently halogen, —(CH₂)₀₋₂R^(), -(haloR^()), —(CH₂)₀₋₂OH, —(CH₂)₀₋₂OR^(), —(CH₂)₀₋₂CH(OR^())₂; —O(haloR^()), —CN, —N₃, —(CH₂)₀₋₂C(O)R^(), —(CH₂)₀₋₂C(O)OH, —(CH₂)₀₋₂C(O)OR^(), —(CH₂)₀₋₄C(O)N(R^(∘))₂; —(CH₂)₀₋₂SR^(), —(CH₂)₀₋₂SH, —(CH₂)₀₋₂NH₂, —(CH₂)₀₋₂NHR^(), —(CH₂)₀₋₂NR^() ₂, —NO₂, —SiR^() ₃, —OSiR^() ₃, —C(O)SR^(), —(C₁₋₄ straight or branched alkylene)C(O)OR^(), or —SSR^() wherein each R^() is unsubstituted or where preceded by “halo” is substituted only with one or more halogens, and is independently selected from C₁₋₄ aliphatic, —CH₂Ph, —O(CH₂)₀₋₁Ph, or a 5-6-membered saturated, partially unsaturated, or aryl ring having 0-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur. Suitable divalent substituents on a saturated carbon atom of R^(∘) include ═O and ═S.

Suitable divalent substituents on a saturated carbon atom of an “optionally substituted” group include the following: ═O, ═S, ═NNR*₂, ═NNHC(O)R*, ═NNHC(O)OR*, ═NNHS(O)₂R*, ═NR*, ═NOR*, —O(C(R*₂))₂₋₃O—, or —S(C(R*₂))₂₋₃S—, wherein each independent occurrence of R* is selected from hydrogen, C₁₋₆ aliphatic which may be substituted as defined below, or an unsubstituted 5-6-membered saturated, partially unsaturated, or aryl ring having 0-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur. Suitable divalent substituents that are bound to vicinal substitutable carbons of an “optionally substituted” group include: —O(CR*₂)₂₋₃O—, wherein each independent occurrence of R* is selected from hydrogen, C₁₋₆ aliphatic which may be substituted as defined below, or an unsubstituted 5-6-membered saturated, partially unsaturated, or aryl ring having 0-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur.

Suitable substituents on the aliphatic group of R* include halogen, —R^(), -(haloR^()), —OH, —OR^(), —O(haloR^()), —CN, —C(O)OH, —C(O)OR^(), —NH₂, —NHR^(), —NR^() ₂, or —NO₂, wherein each R^() is unsubstituted or where preceded by “halo” is substituted only with one or more halogens, and is independently C₁₋₄ aliphatic, —CH₂Ph, —O(CH₂)₀₋₁Ph, or a 5-6-membered saturated, partially unsaturated, or aryl ring having 0-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur.

Suitable substituents on a substitutable nitrogen of an “optionally substituted” group include —R^(†), —NR^(†) ₂, —C(O)R^(†), —C(O)OR^(†), —C(O)C(O)R^(†), —C(O)CH₂C(O)R^(†), —S(O)₂R^(†), S(O)₂NR^(†) ₂, —C(S)NR^(†) ₂, —C(NH)NR^(†) ₂, or —N(R^(†))S(O)₂R^(†); wherein each R^(†) is independently hydrogen, C₁₋₆ aliphatic which may be substituted as defined below, unsubstituted —OPh, or an unsubstituted 5-6-membered saturated, partially unsaturated, or aryl ring having 0-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or, notwithstanding the definition above, two independent occurrences of R^(†), taken together with their intervening atom(s) form an unsubstituted 3-12-membered saturated, partially unsaturated, or aryl mono- or bicyclic ring having 0-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur.

Suitable substituents on the aliphatic group of R^(†) are independently halogen, —R^(), -(haloR^()), —OH, —OR^(), —O(haloR^()), —CN, —C(O)OH, —C(O)OR^(), —NH₂, —NHR^(), —NR^() ₂, or —NO₂, wherein each R^() is unsubstituted or where preceded by “halo” is substituted only with one or more halogens, and is independently C₁ aliphatic, —CH₂Ph, —O(CH₂)₀₋₁Ph, or a 5-6-membered saturated, partially unsaturated, or aryl ring having 0-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur.

When substituents are described herein, the term “radical” or “optionally substituted radical” is sometimes used. In this context, “radical” means a moiety or functional group having an available position for attachment to the structure on which the substituent is bound. In general the point of attachment would bear a hydrogen atom if the substituent were an independent neutral molecule rather than a substituent. The terms “radical” or “optionally-substituted radical” in this context are thus interchangeable with “group” or “optionally-substituted group”.

As used herein, the “term head-to-tail” or “HT”, refers to the regiochemistry of adjacent repeating units in a polymer chain. For example, in the context of poly(propylene carbonate) (PPC), the term head-to-tail based on the three regiochemical possibilities depicted below:

The term head-to-tail ratio (H:T) refers to the proportion of head-to-tail linkages to the sum of all other regiochemical possibilities. With respect to the depiction of polymer structures, while a specific regiochemical orientation of monomer units may be shown in the representations of polymer structures herein, this is not intended to limit the polymer structures to the regiochemical arrangement shown but is to be interpreted to encompass all regiochemical arrangements including that depicted, the opposite regiochemistry, random mixtures, isotactic materials, syndiotactic materials, racemic materials, and/or enantioenriched materials and combinations of any of these unless otherwise specified.

As used herein the term “alkoxylated” means that one or more functional groups on a molecule (usually the functional group is an alcohol, amine, or carboxylic acid, but is not strictly limited to these) has appended to it a hydroxy-terminated alkyl chain. Alkoxylated compounds may comprise a single alkyl group or they may be oligomeric moieties such as hydroxyl-terminated polyethers. Alkoxylated materials can be derived from the parent compounds by treatment of the functional groups with epoxides.

As used herein, the term “isocyanate index” means the excess of isocyanate over the theoretical amount for (1:1) reaction with all active protons in a polyurethane composition, expressed in percentage terms (i.e. 1:1=100). Thus, isocyanate index=100×(Actual amount of isocyanate used)/(Theoretical amount of isocyanate required)

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows the hardness and tensile strength of an adhesive composition of the present invention in comparison to adhesive formulations based on commercial polyester or polycarbonate polyols.

FIG. 2 shows a spider graph showing several properties of an adhesive composition of the present invention in comparison to adhesive formulations based on commercial polycarbonate polyols.

FIG. 3 shows the adhesion to a range of substrates of an adhesive composition of the present invention.

FIG. 4 shows the strength retention at elevated temperatures of an adhesive composition of the present invention in comparison to adhesive formulations based on commercial polyester or polycarbonate polyols.

FIG. 5 shows the solvent resistance of an adhesive composition of the present invention in comparison to adhesive formulations based on commercial polyester or polycarbonate polyols.

FIG. 6 shows the chemical resistance profile of an adhesive composition of the present invention.

FIG. 7 shows the transparency of polyurethane composition of the present invention in comparison to formulations based on commercial polycarbonate polyols.

FIG. 8 shows the strength and elongation of several blended adhesive formulations of the present invention.

DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS

In one aspect, the present invention encompasses polymer compositions comprising aliphatic polycarbonate chains cross-linked or chain extended through urethane linkages. In certain embodiments, these polymer compositions comprise polyurethane adhesives.

The field of polyurethane adhesive manufacture and formulation is well advanced. In some embodiments, the novel materials presented herein are formulated, processed, and/or used according to methods well known in the art. Combining knowledge of the art, with the disclosure and teachings herein, the skilled artisan will readily apprehend variations, modifications and applications of the inventive compositions and methods and such variations are specifically encompassed herein. The following references contain information on the formulation, manufacture and uses of polyurethane adhesives generally, the entire content of each of these references is incorporated herein by reference.

-   Polyurethanes: Coatings Adhesives and Sealants, Ulrich     Maeier-Westhues, 2007 (ISBN 3-87870-334-1) -   The Polyurethanes Book, J. Wiley & Sons, 2003 (ISBN 978-0470850411) -   Szycher's Handbook of Polyurethanes, CRC Press LLC, 1999 (ISBN     0-8493-0602-7) -   Polyurethane Elastomers: From Morphology to Mechanical Aspects,     Springer-Verlag/Wein, 2011 (ISBN 978-3-7091-0513-9) -   Szycher's Handbook of Polyurethanes, CRC Press LLC, 1999 (ISBN     0-8493-0602-7) -   Polyurethane Handbook, Hanser, 1994 (ISBN 1569901570)

In certain embodiments, the polyurethane compositions of the present invention are derived by combining two compositions: a first composition comprising one or more isocyanate compounds optionally containing diluents, solvents, coreactants and the like, and a second composition comprising one or more aliphatic polycarbonate polyols optionally with additional reactants, solvents, catalysts, or additives. These compositions may be formulated separately and then combined or all components of the finished polyurethane composition may be combined in a single step. Before fully describing these compositions, the polyols and isocyanates from which they are formulated will be more fully described.

I. ALIPHATIC POLYCARBONATE POLYOLS

This section describes some of the aliphatic polycarbonate polyols that have utility in making compositions of the present invention. In certain embodiments, compositions of the present invention comprise aliphatic polycarbonate polyols derived from the copolymerization of one or more epoxides and carbon dioxide. Examples of suitable polyols, as well as methods of making them are disclosed in PCT publication WO2010/028362 the entirety of which is incorporated herein by reference.

It is advantageous for many of the embodiments described herein that the aliphatic polycarbonate polyols used have a high percentage of reactive end groups. Such reactive end-groups are typically hydroxyl groups, but other reactive functional groups may be present if the polyols are treated to modify the chemistry of the end groups, such modified materials may terminate in amino groups, thiol groups, alkene groups, carboxylate groups, isocyanate groups, silyl groups, epoxy groups and the like. For purposes of this invention, the term ‘aliphatic polycarbonate polyol’ includes both traditional hydroxy-terminated materials as well as these end-group modified compositions.

In certain embodiments, at least 90% of the end groups of the polycarbonate polyol used are reactive end groups. In certain embodiments, at least 95%, at least 96%, at least 97% or at least 98% of the end groups of the polycarbonate polyol used are reactive end groups. In certain embodiments, more than 99%, more than 99.5%, more than 99.7%, or more than 99.8% of the end groups of the polycarbonate polyol used are reactive end groups. In certain embodiments, more than 99.9% of the end groups of the polycarbonate polyol used are reactive end groups.

In certain embodiments, at least 90% of the end groups of the polycarbonate polyol used are —OH groups. In certain embodiments, at least 95%, at least 96%, at least 97% or at least 98% of the end groups of the polycarbonate polyol used are —OH groups. In certain embodiments, more than 99%, more than 99.5%, more than 99.7%, or more than 99.8% of the end groups of the polycarbonate polyol used are —OH groups. In certain embodiments, more than 99.9% of the end groups of the polycarbonate polyol used are —OH groups.

Another way of expressing the —OH end-group content of a polyol composition is by reporting its OH# which is measured using methods well known in the art. In certain embodiments, the aliphatic polycarbonate polyols used in the present invention have an OH# greater than about 20. In certain embodiments, the aliphatic polycarbonate polyols utilized in the present invention have an OH# greater than about 40. In certain embodiments, the aliphatic polycarbonate polyols have an OH# greater than about 50, greater than about 75, greater than about 100, or greater than about 120.

In certain embodiments, it is advantageous if the aliphatic polycarbonate polyol compositions have a substantial proportion of primary hydroxyl end groups. These are the norm for compositions comprising poly(ethylene carbonate), but for polyols derived from the copolymerization of substituted epoxides with CO₂, it is common for some or most of the chain ends to consist of secondary hydroxyl groups. In certain embodiments, such polyols are treated to increase the proportion of primary —OH end groups. This may be accomplished by reacting the secondary hydroxyl groups with reagents such as ethylene oxide, reactive lactones, and the like. In certain embodiments, the aliphatic polycarbonate polyols are treated with beta lactones, caprolactone and the like to introduce primary hydroxyl end groups. In certain embodiments, the aliphatic polycarbonate polyols are treated with ethylene oxide to introduce primary hydroxyl end groups.

In certain embodiments, aliphatic polycarbonate chains comprise a copolymer of carbon dioxide and one or more epoxides. In certain embodiments, aliphatic polycarbonate chains comprise a copolymer of carbon dioxide and ethylene oxide. In certain embodiments, aliphatic polycarbonate chains comprise a copolymer of carbon dioxide and propylene oxide. In certain embodiments, aliphatic polycarbonate chains comprise a copolymer of carbon dioxide and 1,2-butene oxide and/or 1,2-hexene oxide. In certain embodiments, aliphatic polycarbonate chains comprise a copolymer of carbon dioxide and cyclohexene oxide. In certain embodiments, aliphatic polycarbonate chains comprise a copolymer of carbon dioxide and cyclopentene oxide. In certain embodiments, aliphatic polycarbonate chains comprise a copolymer of carbon dioxide and 3-vinyl cyclohexene oxide. In certain embodiments, aliphatic polycarbonate chains comprise a copolymer of carbon dioxide and 3-ethyl cyclohexene oxide.

In certain embodiments, aliphatic polycarbonate chains comprise a terpolymer of carbon dioxide and ethylene oxide along with one or more additional epoxides selected from the group consisting of propylene oxide, 1,2-butene oxide, 2,3-butene oxide, cyclohexene oxide, 3-vinyl cyclohexene oxide, 3-ethyl cyclohexene oxide, cyclopentene oxide, epichlorohydrin, glicydyl esters, glycidyl ethers, styrene oxides, and epoxides of higher alpha olefins. In certain embodiments, such terpolymers contain a majority of repeat units derived from ethylene oxide with lesser amounts of repeat units derived from one or more additional epoxides. In certain embodiments, terpolymers contain about 50% to about 99.5% ethylene oxide-derived repeat units. In certain embodiments, terpolymers contain greater than about 60% ethylene oxide-derived repeat units. In certain embodiments, terpolymers contain greater than 75% ethylene oxide-derived repeat units. In certain embodiments, terpolymers contain greater than 80% ethylene oxide-derived repeat units. In certain embodiments, terpolymers contain greater than 85% ethylene oxide-derived repeat units. In certain embodiments, terpolymers contain greater than 90% ethylene oxide-derived repeat units. In certain embodiments, terpolymers contain greater than 95% ethylene oxide-derived repeat units.

In embodiments, the aliphatic polycarbonate chains comprise a copolymer of carbon dioxide and propylene oxide along with one or more additional epoxides selected from the group consisting of ethylene oxide, 1,2-butene oxide, 2,3-butene oxide, cyclohexene oxide, 3-vinyl cyclohexene oxide, cyclopentene oxide, epichlorohydrin, glicydyl esters, glycidyl ethers, styrene oxides, and epoxides of higher alpha olefins. In certain embodiments, such terpolymers contain a majority of repeat units derived from propylene oxide with lesser amounts of repeat units derived from one or more additional epoxides. In certain embodiments, terpolymers contain about 50% to about 99.5% propylene oxide-derived repeat units. In certain embodiments, terpolymers contain greater than 60% propylene oxide-derived repeat units. In certain embodiments, terpolymers contain greater than 75% propylene oxide-derived repeat units. In certain embodiments, terpolymers contain greater than 80% propylene oxide-derived repeat units. In certain embodiments, terpolymers contain greater than 85% propylene oxide-derived repeat units. In certain embodiments, terpolymers contain greater than 90% propylene oxide-derived repeat units. In certain embodiments, terpolymers contain greater than 95% propylene oxide-derived repeat units.

In certain embodiments, in the polymer compositions described hereinabove, aliphatic polycarbonate chains have a number average molecular weight (M_(n)) in the range of 500 g/mol to about 250,000 g/mol.

In certain embodiments, aliphatic polycarbonate chains have an M_(n) less than about 100,000 g/mol. In certain embodiments, aliphatic polycarbonate chains have an M_(n) less than about 70,000 g/mol. In certain embodiments, aliphatic polycarbonate chains have an M_(n) less than about 50,000 g/mol. In certain embodiments, aliphatic polycarbonate chains have an M_(n) between about 500 g/mol and about 40,000 g/mol. In certain embodiments, aliphatic polycarbonate chains have an M_(n) less than about 25,000 g/mol. In certain embodiments, aliphatic polycarbonate chains have an M_(n) between about 500 g/mol and about 20,000 g/mol. In certain embodiments, aliphatic polycarbonate chains have an M_(n) between about 500 g/mol and about 10,000 g/mol. In certain embodiments, aliphatic polycarbonate chains have an M_(n) between about 500 g/mol and about 5,000 g/mol. In certain embodiments, aliphatic polycarbonate chains have an M_(n) between about 1,000 g/mol and about 5,000 g/mol. In certain embodiments, aliphatic polycarbonate chains have an M_(n) between about 5,000 g/mol and about 10,000 g/mol. In certain embodiments, aliphatic polycarbonate chains have an M_(n) between about 500 g/mol and about 1,000 g/mol. In certain embodiments, aliphatic polycarbonate chains have an M_(n) between about 1,000 g/mol and about 3,000 g/mol. In certain embodiments, aliphatic polycarbonate chains have an M_(n) of about 5,000 g/mol. In certain embodiments, aliphatic polycarbonate chains have an M_(n) of about 4,000 g/mol. In certain embodiments, aliphatic polycarbonate chains have an M_(n) of about 3,000 g/mol. In certain embodiments, aliphatic polycarbonate chains have an M_(n) of about 2,500 g/mol. In certain embodiments, aliphatic polycarbonate chains have an M_(n) of about 2,000 g/mol. In certain embodiments, aliphatic polycarbonate chains have an M_(n) of about 1,500 g/mol. In certain embodiments, aliphatic polycarbonate chains have an M_(n) of about 1,000 g/mol. In certain embodiments, aliphatic polycarbonate chains have an M_(n) of about 750 g/mol. In certain embodiments, aliphatic polycarbonate chains have an M_(n) of about 500 g/mol.

In certain embodiments, the aliphatic polycarbonate polyols used are characterized in that they have a narrow molecular weight distribution. This can be indicated by the polydispersity indices (PDI) of the aliphatic polycarbonate polymers. In certain embodiments, aliphatic polycarbonate compositions have a PDI less than 3. In certain embodiments, aliphatic polycarbonate compositions have a PDI less than 2. In certain embodiments, aliphatic polycarbonate compositions have a PDI less than 1.8. In certain embodiments, aliphatic polycarbonate compositions have a PDI less than 1.5. In certain embodiments, aliphatic polycarbonate compositions have a PDI less than 1.4. In certain embodiments, aliphatic polycarbonate compositions have a PDI between about 1.0 and 1.2. In certain embodiments, aliphatic polycarbonate compositions have a PDI between about 1.0 and 1.1.

In certain embodiments, the aliphatic polycarbonate polyols used do not have a narrow PDI, this can be the case if, for example, a polydisperse chain transfer agent is used to initiate an epoxide CO₂ copolymerization, or if a a plurality of aliphatic polycarbonate polyol compositions with different PDIs are blended. In certain embodiments, aliphatic polycarbonate compositions have a PDI greater than 3. In certain embodiments, aliphatic polycarbonate compositions have a PDI greater than 2. In certain embodiments, aliphatic polycarbonate compositions have a PDI greater than 1.8. In certain embodiments, aliphatic polycarbonate compositions have a PDI greater than 1.5. In certain embodiments, aliphatic polycarbonate compositions have a PDI greater than 1.4.

In certain embodiments, aliphatic polycarbonate compositions of the present invention comprise substantially alternating polymers containing a high percentage of carbonate linkages and a low content of ether linkages. In certain embodiments, aliphatic polycarbonate compositions of the present invention are characterized in that, on average in the composition, the percentage of carbonate linkages is 85% or greater. In certain embodiments, aliphatic polycarbonate compositions of the present invention are characterized in that, on average in the composition, the percentage of carbonate linkages is 90% or greater. In certain embodiments, aliphatic polycarbonate compositions of the present invention are characterized in that, on average in the composition, the percentage of carbonate linkages is 91% or greater. In certain embodiments, aliphatic polycarbonate compositions of the present invention are characterized in that, on average in the composition, the percentage of carbonate linkages is 92% or greater. In certain embodiments, aliphatic polycarbonate compositions of the present invention are characterized in that, on average in the composition, the percentage of carbonate linkages is 93% or greater. In certain embodiments, aliphatic polycarbonate compositions of the present invention are characterized in that, on average in the composition, the percentage of carbonate linkages is 94% or greater. In certain embodiments, aliphatic polycarbonate compositions of the present invention are characterized in that, on average in the composition, the percentage of carbonate linkages is 95% or greater. In certain embodiments, aliphatic polycarbonate compositions of the present invention are characterized in that, on average in the composition, the percentage of carbonate linkages is 96% or greater. In certain embodiments, aliphatic polycarbonate compositions of the present invention are characterized in that, on average in the composition, the percentage of carbonate linkages is 97% or greater. In certain embodiments, aliphatic polycarbonate compositions of the present invention are characterized in that, on average in the composition, the percentage of carbonate linkages is 98% or greater. In certain embodiments, aliphatic polycarbonate compositions of the present invention are characterized in that, on average in the composition, the percentage of carbonate linkages is 99% or greater. In certain embodiments, aliphatic polycarbonate compositions of the present invention are characterized in that, on average in the composition, the percentage of carbonate linkages is 99.5% or greater. In certain embodiments, the percentages above exclude ether linkages present in polymerization initiators or chain transfer agents and refer only to the linkages formed during epoxide CO₂ copolymerization.

In certain embodiments, aliphatic polycarbonate compositions of the present invention are characterized in that they contain essentially no ether linkages either within the polymer chains derived from epoxide CO₂ copolymerization or within any polymerization initiators, chain transfer agents or end groups that may be present in the polymer. In certain embodiments, aliphatic polycarbonate compositions of the present invention are characterized in that they contain, on average, less than one ether linkage per polymer chain within the composition. In certain embodiments, aliphatic polycarbonate compositions of the present invention are characterized in that they contain essentially no ether linkages.

In certain embodiments where an aliphatic polycarbonate is derived from mono-substituted epoxides (e.g. such as propylene oxide, 1,2-butylene oxide, epichlorohydrin, epoxidized alpha olefins, or a glycidol derivative), the aliphatic polycarbonate is characterized in that it is regioregular. Regioregularity may be expressed as the percentage of adjacent monomer units that are oriented in a head-to-tail arrangement within the polymer chain. In certain embodiments, aliphatic polycarbonate chains in the inventive polymer compositions have a head-to-tail content higher than about 80%. In certain embodiments, the head-to-tail content is higher than about 85%. In certain embodiments, the head-to-tail content is higher than about 90%. In certain embodiments, the head-to-tail content is greater than about 91%, greater than about 92%, greater than about 93%, greater than about 94%, or greater than about 95%. In certain embodiments, the head-to-tail content of the polymer is as determined by proton or carbon-13 NMR spectroscopy.

In certain embodiments, compositions of the present invention comprise aliphatic polycarbonate polyols having a structure P1:

wherein,

R¹, R², R³, and R⁴ are, at each occurrence in the polymer chain, independently selected from the group consisting of —H, fluorine, an optionally substituted C₁₋₃₀ aliphatic group, and an optionally substituted C₁₋₄₀ heteroaliphatic group, and an optionally substituted aryl group, where any two or more of R¹, R², R³, and R⁴ may optionally be taken together with intervening atoms to form one or more optionally substituted rings optionally containing one or more heteroatoms;

Y is, at each occurrence, independently —H, a reactive group (as defined hereinabove), or a site of attachment to any of the chain-extending moieties or isocyanates described in the classes and subclasses herein;

n is at each occurrence, independently an integer from about 2 to about 50;

is a bond or a multivalent moiety; and

x and y are each independently an integer from 0 to 6, where the sum of x and y is between 2 and 6.

In certain embodiments, the multivalent moiety

embedded within the aliphatic polycarbonate chain is derived from a polyfunctional chain transfer agent having two or more sites from which epoxide/CO₂ copolymerization can occur. In certain embodiments, such copolymerizations are performed in the presence of polyfunctional chain transfer agents as exemplified in published PCT application WO/2009056220. In certain embodiments, such copolymerizations are performed as exemplified in US 2011/0245424. In certain embodiments, such copolymerizations are performed as exemplified in Green Chem. 2011, 13, 3469-3475.

In certain embodiments, a polyfunctional chain transfer agent has a formula:

wherein each of

x, and y is as defined above and described in classes and subclasses herein.

In certain embodiments, aliphatic polycarbonate chains in the inventive polymer compositions are derived from the copolymerization of one or more epoxides with carbon dioxide in the presence of such polyfunctional chain transfer agents as shown in Scheme 2:

In certain embodiments, aliphatic polycarbonate chains in polymer compositions of the present invention comprise chains with a structure P2:

wherein each of R¹, R², R³, R⁴, Y,

and n is as defined above and described in the classes and subclasses herein.

In certain embodiments where aliphatic polycarbonate chains have a structure P2,

is derived from a dihydric alcohol. In such instances

represents the carbon-containing backbone of the dihydric alcohol, while the two oxygen atoms adjacent to

are derived from the —OH groups of the diol. For example, if the polyfunctional chain transfer agent were ethylene glycol, then

would be —CH₂CH₂— and P2 would have the following structure:

In certain embodiments where

is derived from a dihydric alcohol, the dihydric alcohol comprises a C₂₋₄₀ diol. In certain embodiments, the dihydric alcohol is selected from the group consisting of: 1,2-ethanediol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 2,2-dimethylpropane-1,3-diol, 2-butyl-2-ethylpropane-1,3-diol, 2-methyl-2,4-pentane diol, 2-ethyl-1,3-hexane diol, 2-methyl-1,3-propane diol, 1,5-hexanediol, 1,6-hexanediol, 1,8-octanediol, 1,10-decanediol, 1,12-dodecanediol, 2,2,4,4-tetramethylcyclobutane-1,3-diol, 1,3-cyclopentanediol, 1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, 1,4-cyclohexanediethanol, isosorbide, glycerol monoesters, glycerol monoethers, trimethylolpropane monoesters, trimethylolpropane monoethers, pentaerythritol diesters, pentaerythritol diethers, and alkoxylated derivatives of any of these.

In certain embodiments where

is derived from a dihydric alcohol, the dihydric alcohol is selected from the group consisting of: diethylene glycol, triethylene glycol, tetraethylene glycol, higher poly(ethylene glycol), such as those having number average molecular weights of from 220 to about 2000 g/mol, dipropylene glycol, tripropylene glycol, and higher poly(propylene glycol) such as those having number average molecular weights of from 234 to about 2000 g/mol.

In certain embodiments where

is derived from a dihydric alcohol, the dihydric alcohol comprises an alkoxylated derivative of a compound selected from the group consisting of: a diacid, a diol, or a hydroxy acid. In certain embodiments, the alkoxylated derivatives comprise ethoxylated or propoxylated compounds.

In certain embodiments where

is derived from a dihydric alcohol, the dihydric alcohol comprises a polymeric diol. In certain embodiments, a polymeric diol is selected from the group consisting of polyethers, polyesters, hydroxy-terminated polyolefins, polyether-copolyesters, polyether polycarbonates, polycarbonate-copolyesters, polyoxymethylene polymers, and alkoxylated analogs of any of these. In certain embodiments, the polymeric diol has an average molecular weight less than about 2000 g/mol.

In certain embodiments,

is derived from a polyhydric alcohol with more than two hydroxy groups. In embodiments in which

is derived from a polyhydric alcohol with more than two hydroxyl groups, these >2 functional polyols are a component of a polyol mixture containing predominantly polyols with two hydroxyl groups. In certain embodiments, these >2 functional polyols are less than 20% of the total polyol mixture by weight. In certain embodiments, these >2 functional polyols are less than 10% of the total polyol mixture. In certain embodiments, these >2 functional polyols are less than 5% of the total polyol mixture. In certain embodiments, these >2 functional polyols are less than 2% of the total polyol mixture. In certain embodiments, the aliphatic polycarbonate chains in polymer compositions of the present invention comprise aliphatic polycarbonate chains where the moiety

is derived from a triol. In certain embodiments, such aliphatic polycarbonate chains have the structure P3:

wherein each of R¹, R², R³, R⁴, Y,

and n is as defined above and described in classes and subclasses herein.

In certain embodiments where

is derived from a triol, the triol is selected from the group consisting of: glycerol, 1,2,4-butanetriol, 2-(hydroxymethyl)-1,3-propanediol; hexane triols, trimethylol propane, trimethylol ethane, trimethylolhexane, 1,4-cyclohexanetrimethanol, pentaerythritol mono esters, pentaerythritol mono ethers, and alkoxylated analogs of any of these. In certain embodiments, such alkoxylated derivatives comprise ethoxylated or propoxylated compounds.

In certain embodiments,

is derived from an alkoxylated derivative of a trifunctional carboxylic acid or trifunctional hydroxy acid. In certain embodiments, alkoxylated derivatives comprise ethoxylated or propoxylated compounds.

In certain embodiments, where

is derived from a polymeric triol, the polymeric triol is selected from the group consisting of polyethers, polyesters, hydroxy-terminated polyolefins, polyether-copolyesters, polyether polycarbonates, polyoxymethylene polymers, polycarbonate-copolyesters, and alkoxylated analogs of any of these. In certain embodiments, the alkoxylated polymeric triols comprise ethoxylated or propoxylated compounds.

In certain embodiments,

is derived from a polyhydric alcohol with four hydroxy groups. In certain embodiments, aliphatic polycarbonate chains in polymer compositions of the present invention comprise aliphatic polycarbonate chains where the moiety

is derived from a tetraol. In certain embodiments, aliphatic polycarbonate chains in polymer compositions of the present invention comprise chains with the structure P4:

wherein each of R¹, R², R³, R⁴, Y,

and n is as defined above and described in classes and subclasses herein.

In certain embodiments,

is derived from a polyhydric alcohol with more than four hydroxy groups. In certain embodiments,

is derived from a polyhydric alcohol with six hydroxy groups. In certain embodiments, a polyhydric alcohol is dipentaerithrotol or an alkoxylated analog thereof. In certain embodiments, a polyhydric alcohol is sorbitol or an alkoxylated analog thereof. In certain embodiments, aliphatic polycarbonate chains in polymer compositions of the present invention comprise chains with the structure P5:

wherein each of R¹, R², R³, R⁴, Y,

and n is as defined above and described in classes and subclasses herein.

In certain embodiments, aliphatic polycarbonates of the present invention comprise a combination of bifunctional chains (e.g. polycarbonates of formula P2) in combination with higher functional chains (e.g. one or more polycarbonates of formulae P3 to P5).

In certain embodiments,

is derived from a hydroxy acid. In certain embodiments, aliphatic polycarbonate chains in polymer compositions of the present invention comprise chains with the structure P6:

wherein each of R1, R2, R3, R4, Y,

and n is as defined above and described in classes and subclasses herein. In such instances,

represents the carbon-containing backbone of the hydroxy acid, while ester and carbonate linkages adjacent to

are derived from the —CO₂H group and the hydroxy group of the hydroxy acid. For example, if

were derived from 3-hydroxy propanoic acid, then

would be —CH₂CH₂— and P6 would have the following structure:

In certain embodiments,

is derived from an optionally substituted C₂₋₄₀ hydroxy acid. In certain embodiments,

is derived from a polyester. In certain embodiments, such polyesters have a molecular weight less than about 2000 g/mol.

In certain embodiments, a hydroxy acid is an alpha-hydroxy acid. In certain embodiments, a hydroxy acid is selected from the group consisting of: glycolic acid, DL-lactic acid, D-lactic acid, L-lactic, citric acid, and mandelic acid.

In certain embodiments, a hydroxy acid is a beta-hydroxy acid. In certain embodiments, a hydroxy acid is selected from the group consisting of: 3-hydroxypropionic acid, DL 3-hydroxybutyric acid, D-3 hydroxybutyric acid, L-3-hydroxybutyric acid, DL-3-hydroxy valeric acid, D-3-hydroxy valeric acid, L-3-hydroxy valeric acid, salicylic acid, and derivatives of salicylic acid.

In certain embodiments, a hydroxy acid is a α-ω hydroxy acid. In certain embodiments, a hydroxy acid is selected from the group consisting of: of optionally substituted C₃₋₂₀ aliphatic α-ω hydroxy acids and oligomeric esters.

In certain embodiments, a hydroxy acid is selected from the group consisting of:

In certain embodiments,

is derived from a polycarboxylic acid. In certain embodiments, aliphatic polycarbonate chains in polymer compositions of the present invention comprise chains with the structure P7:

wherein each of R¹, R², R³, R⁴, Y,

and n is as defined above and described in classes and subclasses herein, and y′ is an integer from 1 to 5 inclusive.

In embodiments where the aliphatic polycarbonate chains have a structure P7,

represents the carbon-containing backbone (or a bond in the case of oxalic acid) of a polycarboxylic acid, while ester groups adjacent to

are derived from —CO₂H groups of the polycarboxylic acid. For example, if

were derived from succinic acid (HO₂CCH₂CH₂CO₂H), then

would be —CH₂CH₂— and P7 would have the following structure:

wherein each of R¹, R², R³, R⁴, Y, and n is as defined above and described in classes and subclasses herein.

In certain embodiments,

is derived from a dicarboxylic acid. In certain embodiments, aliphatic polycarbonate chains in polymer compositions of the present invention comprise chains with the structure P8:

In certain embodiments,

is selected from the group consisting of: phthalic acid, isophthalic acid, terephthalic acid, maleic acid, succinic acid, malonic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, and azelaic acid.

In certain embodiments,

is derived from a diacid selected from the group consisting of:

In certain embodiments, {circle around (Z)} is derived from a phosphorous-containing molecule. In certain embodiments, {circle around (Z)} has a formula —P(O)(OR)_(k)— where each R is independently an optionally substituted C1-20 aliphatic group or an optionally substituted aryl group and k is 0, 1, or 2.

For example, if

were derived from phenyl phosphite (PhO—P(O)(OH)₂), then

would be —P(O)(OPh)- and P7 would have the following structure:

wherein each of R¹, R², R³, R⁴, Y, and n is as defined above and described in classes and subclasses herein.

In certain embodiments, {circle around (Z)} is derived from a phosphorous-containing molecule selected from the group consisting of:

In certain embodiments, {circle around (Z)} has a formula —P(O)(R)— where R is an optionally substituted C₁₋₂₀ aliphatic group or an optionally substituted aryl group and k is 0, 1, or 2. In certain embodiments, {circle around (Z)} is derived from a phosphorous-containing molecule selected from the group consisting of:

where R^(d) is as defined above.

In certain embodiments, {circle around (Z)} has a formula —PR— where R is an optionally substituted C₁₋₂₀ aliphatic group or an optionally substituted aryl group.

In certain embodiments, each

in the structures herein is independently selected from the group consisting of:

-   wherein each R^(x) is independently an optionally substituted moiety     selected from the group consisting of C₂₋₂₀ aliphatic, C₂₋₂₀     heteroaliphatic, 3- to 14-membered carbocyclic, 6- to 10-membered     aryl, 5- to 10-membered heteroaryl, and 3- to 12-membered     heterocyclic.

In certain embodiments, each

in the structures herein is independently selected from the group consisting of:

wherein R^(x) is as defined above and described in classes and subclasses herein.

In certain embodiments, aliphatic polycarbonate chains comprise:

-   -   wherein each of

—Y, and n is as defined above and described in classes and subclasses herein.

In certain embodiments, aliphatic polycarbonate chains comprise

-   -   wherein each of —Y and n is as defined above and described in         classes and subclasses herein.

In certain embodiments, aliphatic polycarbonate chains comprise

-   -   wherein each of —Y and n is as defined above and described in         classes and subclasses herein.

In certain embodiments, aliphatic polycarbonate chains comprise

-   -   wherein each of —Y and n is as defined above and described in         classes and subclasses herein.

In certain embodiments, aliphatic polycarbonate chains comprise

-   -   wherein each of

—Y, and n is as defined above and described in classes and subclasses herein.

In certain embodiments, aliphatic polycarbonate chains comprise

-   -   wherein each of —Y and n is as defined above and described in         classes and subclasses herein.

In certain embodiments, aliphatic polycarbonate chains comprise

-   -   wherein each of

—Y, and n is as defined above and described in classes and subclasses herein.

In certain embodiments, aliphatic polycarbonate chains comprise

-   -   wherein each of —Y and n are is as defined above and described         in classes and subclasses herein.

In certain embodiments, aliphatic polycarbonate chains comprise

-   -   wherein each of

—Y, and n is as defined above and described in classes and subclasses herein.

In certain embodiments, aliphatic polycarbonate chains comprise

-   -   wherein each of —Y and n is as defined above and described in         classes and subclasses herein.

In certain embodiments, aliphatic polycarbonate chains comprise

-   -   wherein each of

—Y, and n is as defined above and described in classes and subclasses herein.

In certain embodiments, aliphatic polycarbonate chains comprise

-   -   wherein each of —Y and n is as defined above and described in         classes and subclasses herein.

In certain embodiments, aliphatic polycarbonate chains comprise

-   -   wherein each of

—Y, R^(x), and n is as defined above and described in classes and subclasses herein.

In certain embodiments, aliphatic polycarbonate chains comprise

-   -   wherein each of —Y, R^(x), and n is as defined above and         described in classes and subclasses herein.

In certain embodiments, aliphatic polycarbonate chains comprise

-   -   wherein each of

—Y, and n is as defined above and described in classes and subclasses herein.

In certain embodiments, aliphatic polycarbonate chains comprise

-   -   wherein each of

—Y, and n are is as defined above and described in classes and subclasses herein; and each

independently represents a single or double bond.

In certain embodiments, aliphatic polycarbonate chains comprise

-   -   wherein each of —Y and n is as defined above and described in         classes and subclasses herein.

In certain embodiments, aliphatic polycarbonate chains comprise

-   -   wherein each of Y,         , and n is as defined above and described in classes and         subclasses herein.

In certain embodiments, aliphatic polycarbonate chains comprise

-   -   wherein each of

R^(x), —Y and n is as defined above and described in classes and subclasses herein.

In certain embodiments, aliphatic polycarbonate chains comprise

-   -   wherein each of —Y, R^(x), and n is as defined above and         described in classes and subclasses herein.

In certain embodiments, aliphatic polycarbonate chains comprise

-   -   wherein each of

—Y, and n is as defined above and described in classes and subclasses herein.

In certain embodiments, aliphatic polycarbonate chains comprise

-   -   wherein each of —Y,         , and n is as defined above and described in classes and         subclasses herein.

In certain embodiments, aliphatic polycarbonate chains comprise

-   -   wherein each of —Y and n is as defined above and described in         classes and subclasses herein.

In certain embodiments, aliphatic polycarbonate chains comprise

-   -   wherein each of —Y,         , and n is as defined above and described in classes and         subclasses herein.

In certain embodiments, aliphatic polycarbonate chains comprise

-   -   wherein each of

—Y, and n is as denied above and described in classes and subclasses herein.

In certain embodiments, aliphatic polycarbonate chains comprise

-   -   wherein each of —Y and n is as defined above and described in         classes and subclasses herein.

In certain embodiments, in polycarbonates of structures P2a, P2c, P2d, P2f, P2h, P2j, P2l, P2l-a, P2n, P2p, and P2r, {circle around (Z)} is selected from the group consisting of: ethylene glycol; diethylene glycol, triethylene glycol, 1,3 propane diol; 1,4 butane diol, hexylene glycol, 1,6 hexane diol, propylene glycol, dipropylene glycol, tripopylene glycol, and alkoxylated derivatives of any of these.

For polycarbonates comprising repeat units derived from two or more epoxides, such as those represented by structures P2f through P2r, depicted above, it is to be understood that the structures drawn may represent mixtures of positional isomers or regioisomers that are not explicitly depicted. For example, the polymer repeat unit adjacent to either end group of the polycarbonate chains can be derived from either one of the two epoxides comprising the copolymers. Thus, while the polymers may be drawn with a particular repeat unit attached to an end group, the terminal repeat units might be derived from either of the two epoxides and a given polymer composition might comprise a mixture of all of the possibilities in varying ratios. The ratio of these end-groups can be influenced by several factors including the ratio of the differ rent epoxides used in the polymerization, the structure of the catalyst used, the reaction conditions used (i.e. temperature pressure, etc.) as well as by the timing of addition of reaction components. Similarly, while the drawings above may show a defined regiochemistry for repeat units derived from substituted epoxides, the polymer compositions will, in some cases, contain mixtures of regioisomers. The regioselectivity of a given polymerization can be influenced by numerous factors including the structure of the catalyst used and the reaction conditions employed. To clarify, this means that the composition represented by structure P2r above, may contain a mixture of several compounds as shown in the diagram below. This diagram shows the isomers graphically for polymer P2r, where the structures below the depiction of the chain show each regio- and positional isomer possible for the monomer unit adjacent to the chain transfer agent and the end groups on each side of the main polymer chain. Each end group on the polymer may be independently selected from the groups shown on the left or right while the central portion of the polymer including the chain transfer agent and its two adjacent monomer units may be independently selected from the groups shown. In certain embodiments, the polymer composition comprises a mixture of all possible combinations of these. In other embodiments, the polymer composition is enriched in one or more of these.

In certain embodiments, the aliphatic polycarbonate polyol is selected from the group consisting of Q1, Q2, Q3, Q4, Q5, Q6, and mixtures of any two or more of these.

-   -   wherein, t is an integer from 1 to 12 inclusive, and R^(t) is         independently at each occurrence —H, or —CH₃.

In certain embodiments, the aliphatic polycarbonate polyol is selected from the group consisting of:

Poly(ethylene carbonate) of formula Q1 having an average molecular weight number of between about 500 g/mol and about 3,000 g/mol, a polydispersity index less than about 1.25, at least 85% carbonate linkages, and at least 98% —OH end groups;

Poly(ethylene carbonate) of formula Q1 having an average molecular weight number of about 500 g/mol, a polydispersity index less than about 1.25, at least 85% carbonate linkages, and at least 98% —OH end groups;

Poly(ethylene carbonate) of formula Q1 having an average molecular weight number of about 1,000 g/mol, a polydispersity index less than about 1.25, at least 85% carbonate linkages, and at least 98% —OH end groups;

Poly(ethylene carbonate) of formula Q1 having an average molecular weight number of about 2,000 g/mol, a polydispersity index less than about 1.25, at least 85% carbonate linkages, and at least 98% —OH end groups;

Poly(ethylene carbonate) of formula Q1 having an average molecular weight number of about 3,000 g/mol, a polydispersity index less than about 1.25, at least 85% carbonate linkages, and at least 98% —OH end groups;

Poly(propylene carbonate) of formula Q2 having an average molecular weight number of between about 500 g/mol and about 3,000 g/mol, a polydispersity index less than about 1.25, at least 95% carbonate linkages, and at least 98% —OH end groups;

Poly(propylene carbonate) of formula Q2 having an average molecular weight number of about 500 g/mol, a polydispersity index less than about 1.25, at least 95% carbonate linkages, and at least 98% —OH end groups;

Poly(propylene carbonate) of formula Q2 having an average molecular weight number of about 1,000 g/mol, a polydispersity index less than about 1.25, at least 95% carbonate linkages, and at least 98% —OH end groups;

Poly(propylene carbonate) of formula Q2 having an average molecular weight number of about 2,000 g/mol, a polydispersity index less than about 1.25, at least 95% carbonate linkages, and at least 98% —OH end groups;

Poly(propylene carbonate) of formula Q2 having an average molecular weight number of about 3,000 g/mol, a polydispersity index less than about 1.25, at least 95% carbonate linkages, and at least 98% —OH end groups;

Poly(ethylene-co-propylene carbonate) of formula Q3 having an average molecular weight number of between about 500 g/mol and about 3,000 g/mol, a polydispersity index less than about 1.25, at least 90% carbonate linkages, and at least 98% —OH end groups;

Poly(ethylene-co-propylene carbonate) of formula Q3 having an average molecular weight number of about 500 g/mol, a polydispersity index less than about 1.25, at least 90% carbonate linkages, and at least 98% —OH end groups;

Poly(ethylene-co-propylene carbonate) of formula Q3 having an average molecular weight number of about 1,000 g/mol, a polydispersity index less than about 1.25, at least 90% carbonate linkages, and at least 98% —OH end groups;

Poly(ethylene-co-propylene carbonate) of formula Q3 having an average molecular weight number of about 2,000 g/mol (e.g. n is on average between about 10 and about 11), a polydispersity index less than about 1.25, at least 90% carbonate linkages, and at least 98% —OH end groups;

Poly(ethylene-co-propylene carbonate) of formula Q3 having an average molecular weight number of about 3,000 g/mol, a polydispersity index less than about 1.25, at least 95% carbonate linkages, and at least 98% —OH end groups;

Poly(ethylene carbonate) of formula Q4 having an average molecular weight number of between about 500 g/mol and about 3,000 g/mol (e.g. each n is between about 4 and about 16), a polydispersity index less than about 1.25, at least 95% carbonate linkages, and at least 98% —OH end groups;

Poly(ethylene carbonate) of formula Q4 having an average molecular weight number of about 500 g/mol, a polydispersity index less than about 1.25, at least 85% carbonate linkages, and at least 98% —OH end groups;

Poly(ethylene carbonate) of formula Q4 having an average molecular weight number of about 1,000 g/mol, a polydispersity index less than about 1.25, at least 85% carbonate linkages, and at least 98% —OH end groups;

Poly(ethylene carbonate) of formula Q4 having an average molecular weight number of about 2,000 g/mol, a polydispersity index less than about 1.25, at least 85% carbonate linkages, and at least 98% —OH end groups;

Poly(ethylene carbonate) of formula Q4 having an average molecular weight number of about 3,000 g/mol, a polydispersity index less than about 1.25, at least 85% carbonate linkages, and at least 98% —OH end groups.

Poly(propylene carbonate) of formula Q5 having an average molecular weight number of between about 500 g/mol and about 3,000 g/mol, a polydispersity index less than about 1.25, at least 95% carbonate linkages, and at least 98% —OH end groups;

Poly(propylene carbonate) of formula Q5 having an average molecular weight number of about 500 g/mol, a polydispersity index less than about 1.25, at least 95% carbonate linkages, and at least 98% —OH end groups;

Poly(propylene carbonate) of formula Q5 having an average molecular weight number of about 1,000 g/mol, a polydispersity index less than about 1.25, at least 95% carbonate linkages, and at least 98% —OH end groups;

Poly(propylene carbonate) of formula Q5 having an average molecular weight number of about 2,000 g/mol, a polydispersity index less than about 1.25, at least 95% carbonate linkages, and at least 98% —OH end groups;

Poly(propylene carbonate) of formula Q5 having an average molecular weight number of about 3,000 g/mol, a polydispersity index less than about 1.25, at least 95% carbonate linkages, and at least 98% —OH end groups;

Poly(ethylene-co-propylene carbonate) of formula Q6 having an average molecular weight number of between about 500 g/mol and about 3,000 g/mol, a polydispersity index less than about 1.25, at least 90% carbonate linkages, and at least 98% —OH end groups;

Poly(ethylene-co-propylene carbonate) of formula Q6 having an average molecular weight number of about 500 g/mol, a polydispersity index less than about 1.25, at least 90% carbonate linkages, and at least 98% —OH end groups;

Poly(ethylene-co-propylene carbonate) of formula Q6 having an average molecular weight number of about 1,000 g/mol, a polydispersity index less than about 1.25, at least 90% carbonate linkages, and at least 98% —OH end groups;

Poly(ethylene-co-propylene carbonate) of formula Q6 having an average molecular weight number of about 2,000 g/mol (e.g. n is on average between about 10 and about 11), a polydispersity index less than about 1.25, at least 90% carbonate linkages, and at least 98% —OH end groups;

Poly(ethylene-co-propylene carbonate) of formula Q6 having an average molecular weight number of about 3,000 g/mol, a polydispersity index less than about 1.25, at least 95% carbonate linkages, and at least 98% —OH end groups; and Mixtures of any two or more of these.

In certain embodiments, the embedded chain transfer agent {circle around (Z)} is a moiety derived from a polymeric diol or higher polyhydric alcohol. In certain embodiments, such polymeric alcohols are polyether or polyester polyols. In certain embodiments {circle around (Z)} is a polyether polyol comprising ethylene glycol or propylene glycol repeating units (—OCH₂CH₂O—, or —OCH₂CH(CH₃)O—) or combinations of these. In certain embodiments, {circle around (Z)} is a polyester polyol comprising the reaction product of a diol and a diacid, or a material derived from ring-opening polymerization of one or more lactones.

In certain embodiments where {circle around (Z)} comprises a polyether diol, the aliphatic polycarbonate polyol has a structure Q7:

wherein,

R^(q) is at each occurrence in the polymer chain independently —H or —CH₃;

R^(a) is —H, or —CH₃;

q and q′ are independently an integer from about 0 to about 40; and

and n is as defined above and in the examples and embodiments herein.

In certain embodiments, an aliphatic polycarbonate polyol is selected from the group consisting of:

In certain embodiments, where aliphatic polycarbonate polyols comprise compounds conforming to structure Q7, the moiety {circle around (Z)} is derived from a commercially available polyether polyol such as those typically used in the formulation of polyurethane compositions.

In certain embodiments where {circle around (Z)} comprises a polyether diol, the aliphatic polycarbonate polyol has a structure Q8:

wherein,

-   -   c is at each occurrence in the polymer chain independently an         integer from 0 to 6;     -   d is at each occurrence in the polymer chain independently an         integer from 1 to 11; and     -   each of R^(q), n q and q′ is as defined above and in the         examples and embodiments herein.

In certain embodiments, an aliphatic polycarbonate polyol is selected from the group consisting of:

In certain embodiments, were aliphatic polycarbonate polyols comprise compounds conforming to structure Q8, the moiety {circle around (Z)} is derived from a commercially available polyester polyol such as those typically used in the formulation of polyurethane compositions.

II. ISOCYANATE REAGENTS

As described above, the compositions of the present invention comprise higher polymers derived from reactions with isocyanate reagents. The purpose of these isocyanate reagents is to react with the reactive end groups on the aliphatic polycarbonate polyols to form higher molecular weight structures through chain extension and/or cross-linking.

The art of polyurethane synthesis is well advanced and a very large number of isocyanates and related polyurethane precursors are known in the art. While this section of the specification describes isocyanates suitable for use in certain embodiments of the present invention, it is to be understood that it is within the capabilities of one skilled in the art of polyurethane formulation to use alternative isocyanates along with the teachings of this disclosure to formulate additional compositions of matter within the scope of the present invention. Descriptions of suitable isocyanate compounds and related methods can be found in: Chemistry and Technology of Polyols for Polyurethanes Ionescu, Mihail 2005 (ISBN 978-1-84735-035-0), and H. Ulrich, “Urethane Polymers,” Kirk-Othmer Encyclopedia of Chemical Technology, 1997 the entirety of each of which is incorporated herein by reference.

In certain embodiments, the isocyanate reagents comprise two or more isocyanate groups per molecule. In certain embodiments the isocyanate reagents are diisocyanates. In other embodiments, the isocyanate reagents are higher polyisocyanates such as triisocyanates, tetraisocyanates, isocyanate polymers or oligomers, and the like, which are typically a minority component of a mix of predominantly diisocyanates. In certain embodiments, the isocyanate reagents are aliphatic polyisocyanates or derivatives or oligomers of aliphatic polyisocyanates. In other embodiments, the isocyanates are aromatic polyisocyanates or derivatives or oligomers of aromatic polyisocyanates. In certain embodiments, the compositions may comprise mixtures of any two or more of the above types of isocyanates.

In certain embodiments, isocyanate reagents usable for the production of the polyurethane adhesive include aliphatic, cycloaliphatic and aromatic diisocyanate compounds.

Suitable aliphatic and cycloaliphatic isocyanate compounds include, for example, 1,3-trimethylene diisocyanate, 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, 1,9-nonamethylene diisocyanate, 1,10-decamethylene diisocyanate, 1,4-cyclohexane diisocyanate, isophorone diisocyanate, 4,4,′-dicyclohexylmethane diisocyanate, 2,2′-diethylether diisocyanate, hydrogenated xylylene diisocyanate, and hexamethylene diisocyanate-biuret.

The aromatic isocyanate compounds include, for example, p-phenylene diisocyanate, tolylene diisocyanate, xylylene diisocyanate, 4,4′-diphenyl diisocyanate, 2,4′-diphenylmethane diisocyanate, 1,5-naphthalene diisocyanate, 4,4′-diphenylmethane diisocyanate (MDI), 3,3′-methyleneditolylene-4,4′-diisocyanate, tolylenediisocyanate-trimethylolpropane adduct, triphenylmethane triisocyanate, 4,4′-diphenylether diisocyanate, tetrachlorophenylene diisocyanate, 3,3′-dichloro-4,4′-diphenylmethane diisocyanate, and triisocyanate phenylthiophosphate.

In certain embodiments, the isocyanate compound employed comprises one or more of: 4,4′-diphenylmethane diisocyanate, 1,6-hexamethylene hexamethylene diisocyanate and isophorone diisocyanate. In certain embodiments, the isocyanate compound employed is 4,4′-diphenylmethane diisocyanate. The above-mentioned diisocyanate compounds may be employed alone or in mixtures of two or more thereof.

In certain embodiments, an isocyanate reagent is selected from the group consisting of: 1,6-hexamethylaminediisocyanate (HDI), isophorone diisocyanate (IPDI), 4,4′ methylene-bis(cyclohexyl isocyanate) (H₁₂MDI), 2,4-toluene diisocyanate (TDI), 2,6-toluene diisocyanate (TDI), diphenylmethane-4,4′-diisocyanate (MDI), diphenylmethane-2,4′-diisocyanate (MDI), xylylene diisocyanate (XDI), 1,3-Bis(isocyanatomethyl)cyclohexane (H6-XDI), 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate (TMDI), m-tetramethylxylylene diisocyanate (TMXDI), p-tetramethylxylylene diisocyanate (TMXDI), isocyanatomethyl-1,8-ictane diisocyanate (TIN), triphenylmethane-4,4′,4″triisocyanate, Tris(p-isocyanatomethyl)thiosulfate, 1,3-Bis(isocyanatomethyl)benzene, 1,4-tetramethylene diisocyanate, trimethylhexane diisocyanate, 1,6-hexamethylene diisocyanate, 1,4-cyclohexyl diisocyanate, lysine diisocyanate, HDI allophonate trimer, HDI urethdione and HDI-trimer and mixtures of any two or more of these.

In certain embodiments, an isocyanate reagent is selected from the group consisting of 4,4′-diphenylmethane diisocyanate, 1,6-hexamethylene diisocyanate and isophorone diisocyanate. In certain embodiments, an isocyanate reagent is 4,4′-diphenylmethane diisocyanate. certain embodiments, an isocyanate reagent is 1,6-hexamethylene diisocyanate. certain embodiments, an isocyanate reagent is isophorone diisocyanate.

Isocyanates suitable for certain embodiments of the present invention are available commercially under various trade names. Examples of suitable commercially available isocyanates include materials sold under trade names: Desmodur® (Bayer Material Science), Tolonate® (Perstorp), Takenate® (Takeda), Vestanat® (Evonik), Desmotherm® (Bayer Material Science), Bayhydur® (Bayer Material Science), Mondur (Bayer Material Science), Suprasec (Huntsman Inc.), Lupranate® (BASF), Trixene (Baxenden), Hartben® (Benasedo), Ucopol® (Sapici), and Basonat® (BASF). Each of these trade names encompasses a variety of isocyanate materials available in various grades and formulations. The selection of suitable commercially-available isocyanate materials as reagents to produce polyurethane compositions for a particular application is within the capability of one skilled in the art of polyurethane coating technology using the teachings and disclosure of this patent application along with the information provided in the product data sheets supplied by the above-mentioned suppliers.

Additional isocyanates suitable for certain embodiments of the present invention are sold under the trade name Lupranate® (BASF). In certain embodiments, the isocyanates are selected from the group consisting of the materials shown in Table 1, and typically from the subset of this list that are between 1.95 and 2.1 functional isocyanates:

TABLE 1 % Nominal Products Description NCO Funct. Lupranate M 4,4′ MDI 33.5 2 Lupranate MS 4,4′ MDI 33.5 2 Lupranate MI 2,4′ and 4,4′ MDI Blend 33.5 2 Lupranate LP30 Liquid Pure 4,4′ MDI 33.1 2 Lupranate 227 Monomeric/Modified MDI Blend 32.1 2 Carbodimide Modified MDI Lupranate 5143 Carbodiimide Modified 4,4′ MDI 29.2 2.2 Lupranate Carbodiimide Modified 4,4′ MDI 29.5 2.2 MM103 Lupranate 219 Carbodiimide Modified 4,4′ MDI 29.2 2.2 Lupranate 81 Carbodiimide Modified MDI 29.5 2.2 Lupranate 218 Carbodiimide Modified MDI 29.5 2.2 Polymeric MDI (PMDI) Lupranate M10 Low Funct. Polymeric 31.7 2.2 Lupranate Polymeric MDI Variant 31.5 2.7 R2500U Lupranate M20S Mid-Functionality Polymeric 31.5 2.7 Lupranate Mid-Functionality Polymeric 31.5 2.7 M20FB Lupranate M70L High-Functionality Polymeric 31 3 Lupranate M200 High-Functionality Polymeric 30 3.1 Polymeric MDI Blends and Derivatives Lupranate 241 Low Functionality Polymeric 32.6 2.3 Lupranate 230 Low Viscosity Polymeric 32.5 2.3 Lupranate 245 Low Viscosity Polymeric 32.3 2.3 Lupranate Mid Functionality Polymeric 32.3 2.4 TF2115 Lupranate 78 Mid Functionality Polymeric 32 2.3 Lupranate 234 Low Functionality Polymeric 32 2.4 Lupranate 273 Low Viscosity Polymeric 32 2.5 Lupranate 266 Low Viscosity Polymeric 32 2.5 Lupranate 261 Low Viscosity Polymeric 32 2.5 Lupranate 255 Low Viscosity Polymeric 31.9 2.5 Lupranate 268 Low Viscosity Polymeric 30.6 2.4 Select MDI Prepolymers Lupranate 5010 Higher Functional Prepolymer 28.6 2.3 Lupranate 223 Low Visc. Derivative of Pure MDI 27.5 2.2 Lupranate 5040 Mid Functional, Low Viscosity 26.3 2.1 Lupranate 5110 Polymeric MDI Prepolymer 25.4 2.3 Lupranate MP102 4,4′ MDI Prepolymer 23 2 Lupranate 5090 Special 4,4′ MDI Prepolymer 23 2.1 Lupranate 5050 Mid Functional, Mid NCO Prepol 21.5 2.1 Lupranate 5030 Special MDI Prepolymer 18.9 NA Lupranate 5080 2,4′-MDI Enhanced Prepolymer 15.9 2 Lupranate 5060 Low Funct, Higher MW Prepol 15.5 2 Lupranate 279 Low Funct, Special Prepolymer 14 2 Lupranate 5070 Special MDI Prepolymer 13 2 Lupranate 5020 Low Functionality, Low NCO 9.5 2 Toluene Diisocyanate (TDI) Lupranate T80- 80/20: 2,4/2,6 TDI 48.3 2 Lupranate T80- High Acidity TDI 48.3 2 Lupranate 8020 80/20: TDI/Polymeric MDI 44.6 2.1

Other isocyanates suitable for certain embodiments of the present invention are sold under the trade name Desmodur® available from Bayer Material Science. In certain embodiments, the isocyanates are selected from the group consisting of the materials shown in Table 2, and typically from the subset of this list that are between 1.95 and 2.1 functional isocyanates:

TABLE 2 Trade Name Description Desmodur ® 2460 M Monomeric diphenylmethane diisocyanate with high 2,4′- isomer content Desmodur ® 44 M A monomeric diphenylmethane-4,4′-diisocyanate (MDI). Desmodur ® 44 MC Desmodur 44 MC Flakes is a monomeric diphenylmethane-4,4′- diisocyanate (MDI). Desmodur ® BL 1100/1 Blocked aromatic polyisocyanate based on TDI Desmodur ® BL 1265 MPA/X Blocked aromatic polyisocyanate based on TDI Desmodur ® BL 3175 SN Blocked, aliphatic polyisocyanate based on HDI Desmodur ® BL 3272 MPA Blocked aliphatic polyisocyanate based on HDI Desmodur ® BL 3370 MPA Blocked aliphatic polyisocyanate based on HDI Desmodur ® BL 3475 BA/SN Aliphatic crosslinking stoving urethane resin based on HDI/IPDI Desmodur ® BL 3575/1 MPA/SN Blocked aliphatic polyisocyanate based on HDI Desmodur ® BL 4265 SN Blocked, aliphatic polyisocyanate based on IPDI Desmodur ® BL 5375 Blocked aliphatic polyisocyanate based on H 12 MDI Desmodur ® CD-L Desmodur CD-L is a modified isocyanate based on diphenylmethane-4,4′-diisocyanate. Desmodur ® CD-S Desmodur CD-S is a modified isocyanate based on diphenylmethane-4,4′-diisocyanate. Desmodur ® D XP 2725 Hydrophilically modified polyisocyanate Desmodur ® DA-L Hydrophilic aliphatic polyisocyanate based on hexamethylene diisocyanate Desmodur ® DN Aliphatic polyisocyanate of low volatility Desmodur ® E 1160 Aromatic polyisocyanate prepolymer based on toluene diisocyanate Desmodur ® E 1361 BA Aromatic polyisocyanate prepolymer based on toluylene diisocyanate Desmodur ® E 1361 MPA/X Aromatic polyisocyanate prepolymer based on toluene diisocyanate Desmodur ® E 14 Aromatic polyisocyanate prepolymer based on toluene diisocyanate Desmodur ® E 15 Aromatic polyisocyanate prepolymer based on toluene diisocyanate. Desmodur ® E 1660 Aromatic polyisocyanate prepolymer based on toluene diisocyanate. Desmodur ® E 1750 PR Polyisocyanate prepolymer based on toluene diisocyanate Desmodur ® E 20100 Modified polyisocyanate prepolymer based on diphenylmethane diisocyanate. Desmodur ® E 21 Aromatic polyisocyanate prepolymer based on diphenylmethane diisocyanate (MDI). Desmodur ® E 2190 X Aromatic polyisocyanate prepolymer based on diphenylmethane diisocyanate (MDI) Desmodur ® E 22 Aromatic polyisocyanate prepolymer based on diphenylmethane diisocyanate. Desmodur ® E 2200/76 Desmodur E 2200/76 is a prepolymer based on (MDI) with isomers. Desmodur ® E 23 Aromatic polyisocyanate prepolymer based on diphenylmethane diisocyanate (MDI). Desmodur ® E 29 Polyisocyanate prepolymer based on diphenylmethane diisocyanate. Desmodur ® E 305 Desmodur E 305 is a largely linear aliphatic NCO prepolymer based on hexamethylene diisocyanate. Desmodur ® E 3265 MPA/SN Aliphatic polyisocyanate prepolymer based on hexamethylene diisocyanate (HDI) Desmodur ® E 3370 Aliphatic polyisocyanate prepolymer based on hexamethylene diisocyanate Desmodur ® E XP 2605 Polyisocyanate prepolymer based on toluene diisocyanate and diphenylmethan diisocyanate Desmodur ® E XP 2605 Polyisocyanate prepolymer based on toluene diisocyanate and diphenylmethan diisocyanate Desmodur ® E XP 2715 Aromatic polyisocyanate prepolymer based on 2,4′- diphenylmethane diisocyanate (2,4′-MDI) and a hexanediol Desmodur ® E XP 2723 Aromatic polyisocyanate prepolymer based on diphenylmethane diisocyanate (MDI). Desmodur ® E XP 2726 Aromatic polyisocyanate prepolymer based on 2,4′- diphenylmethane diisocyanate (2,4′-MDI) Desmodur ® E XP 2727 Aromatic polyisocyanate prepolymer based on diphenylmethane diisocyanate. Desmodur ® E XP 2762 Aromatic polyisocyanate prepolymer based on diphenylmethane diisocyanate (MDI). Desmodur ® H Monomeric aliphatic diisocyanate Desmodur ® HL Aromatic/aliphatic polyisocyanate based on toluylene diisocyanate/hexamethylene diisocyanate Desmodur ® I Monomeric cycloaliphatic diisocyanate. Desmodur ® IL 1351 Aromatic polyisocyanate based on toluene diisocyanate Desmodur ® IL 1451 Aromatic polyisocyanate based on toluene diisocyanate Desmodur ® IL BA Aromatic polyisocyanate based on toluene diisocyanate Desmodur ® IL EA Aromatic polyisocyante resin based on toluylene diisocyanate Desmodur ® L 1470 Aromatic polyisocyanate based on toluene diisocyanate Desmodur ® L 67 BA Aromatic polyisocyanate based on tolulene diisocyanate Desmodur ® L 67 MPA/X Aromatic polyisocyanate based on tolulene diisocyanate Desmodur ® L 75 Aromatic polyisocyanate based on tolulene diisocyanate Desmodur ® LD Low-functionality isocyanate based on hexamethylene diisocyanate (HDI) Desmodur ® LS 2424 Monomeric diphenylmethane diisocyanate with high 2,4′- isomer content Desmodur ® MT Polyisocyanate prepolymer based on diphenylmethane diisocyanate Desmodur ® N 100 Aliphatic polyisocyanate (HDI biuret) Desmodur ® N 3200 Aliphatic polyisocyanate (low-viscosity HDI biuret) Desmodur ® N 3300 Aliphatic polyisocyanate (HDI trimer) Desmodur ® N 3368 BA/SN Aliphatic polyisocyanate (HDI trimer) Desmodur ® N 3368 SN Aliphatic polyisocyanate (HDI trimer) Desmodur ® N 3386 BA/SN Aliphatic polyisocyanate (HDI trimer) Desmodur ® N 3390 BA Aliphatic polyisocyanate (HDI trimer) Desmodur ® N 3390 BA/SN Aliphatic polyisocyanate (HDI trimer) Desmodur ® N 3400 Aliphatic polyisocyanate (HDI uretdione) Desmodur ® N 3600 Aliphatic polyisocyanate (low-viscosity HDI trimer) Desmodur ® N 3790 BA Aliphatic polyisocyanate (high functional HDI trimer) Desmodur ® N 3800 Aliphatic polyisocyanate (flexibilizing HDI trimer) Desmodur ® N 3900 Low-viscosity, aliphatic polyisocyanate resin based on hexamethylene diisocyanate Desmodur ® N 50 BA/MPA Aliphatic polyisocyanate (HDI biuret) Desmodur ® N 75 BA Aliphatic polyisocyanate (HDI biuret) Desmodur ® N 75 MPA Aliphatic polyisocyanate (HDI biuret) Desmodur ® N 75 MPA/X Aliphatic polyisocyanate (HDI biuret) Desmodur ® NZ 1 Aliphatic polyisocyanate Desmodur ® PC-N Desmodur PC-N is a modified diphenyl-methane-4,4′- diisocyanate (MDI). Desmodur ® PF Desmodur PF is a modified diphenyl-methane-4,4′-diisocyanate (MDI). Desmodur ® PL 340, 60% BA/SN Blocked aliphatic polyisocyanate based on IPDI Desmodur ® PL 350 Blocked aliphatic polyisocyanate based on HDI Desmodur ® RC Solution of a polyisocyanurate of toluene diisocyanate (TDI) in ethyl acetate. Desmodur ® RE Solution of triphenylmethane-4,4′,4″-triisocyanate in ethyl acetate Desmodur ® RFE Solution of tris(p-isocyanatophenyl) thiophosphate in ethyl acetate Desmodur ® RN Solution of a polyisocyanurate with aliphatic and aromatic NCO groups in ethyl acetate. Desmodur ® T 100 Pure 2,4′-toluene diisocyanate (TDI) Desmodur ® T 65 N 2,4- and 2,6-toluene diisocyanate (TDI) in the ratio 67:33 Desmodur ® T 80 2,4- and 2,6-toluene diisocyanate (TDI) in the ratio 80:20 Desmodur ® T 80 P 2,4- and 2,6-toluene diisocyanate (TDI) in the ratio 80:20 with an increased content of hydrolysable chlorine Desmodur ® VH 20 N Polyisocyanate based on diphenylmethane diisocyanate Desmodur ® VK Desmodur VK products re mixtures of diphenylmethane-4,4′- diisocyanate (MDI) with isomers and higher functional Desmodur ® VKP 79 Desmodur VKP 79 is a modified diphenylmethane-4,4′- diisocyanate (MDI) with isomers and homologues. Desmodur ® VKS 10 Desmodur VKS 10 is a mixture of diphenylmethane-4,4′- diisocyanate (MDI) with isomers and higher functional Desmodur ® VKS 20 Desmodur VKS 20 is a mixture of diphenylmethane-4,4′- diisocyanate (MDI) with isomers and higher functional Desmodur ® VKS 20 F Desmodur VKS 20 F is a mixture of diphenylmethane-4,4′- diisocyanate (MDI) with isomers and higher functional Desmodur ® VKS 70 Desmodur VKS 70 is a mixture of diphenylmethane-4,4′- diisocyanate (MDI) with isomers and homologues. Desmodur ® VL Aromatic polyisocyanate based on diphenylmethane diisocyanate Desmodur ® VP LS 2078/2 Blocked aliphatic polyisocyanate based on IPDI Desmodur ® VP LS 2086 Aromatic polyisocyanate prepolymer based on diphenylmethane diisocyanate Desmodur ® VP LS 2257 Blocked aliphatic polyisocyanate based on HDI Desmodur ® VP LS 2371 Aliphatic polyisocyanate prepolymer based on isophorone diisocyanate. Desmodur ® VP LS 2397 Desmodur VP LS 2397 is a linear prepolymer based on polypropylene ether glycol and diphenylmethane diisocyanate Desmodur ® W Monomeric cycloaliphatic diisocyanate Desmodur ® W/1 Monomeric cycloaliphatic diisocyanate Desmodur ® XP 2404 Desmodur XP 2404 is a mixture of monomeric polyisocyanates Desmodur ® XP 2406 Aliphatic polyisocyanate prepolymer based on isophorone diisocyanate Desmodur ® XP 2489 Aliphatic polyisocyanate Desmodur ® XP 2505 Desmodur XP 2505 is a prepolymer containing ether groups based on diphenylmethane-4,4′-diisocyanates (MDI) with Desmodur ® XP 2551 Aromatic polyisocyanate based on diphenylmethane diisocyanate Desmodur ® XP 2565 Low-viscosity, aliphatic polyisocyanate resin based on isophorone diisocyanate. Desmodur ® XP 2580 Aliphatic polyisocyanate based on hexamethylene diisocyanate Desmodur ® XP 2599 Aliphatic prepolymer containing ether groups and based on hexamethylene-1,6-diisocyanate (HDI) Desmodur ® XP 2617 Desmodur XP 2617 is a largely linear NCO prepolymer based on hexamethylene diisocyanate. Desmodur ® XP 2665 Aromatic polyisocyanate prepolymer based on diphenylmethane diisocyanate (MDI). Desmodur ® XP 2675 Aliphatic polyisocyanate (highly functional HDI trimer) Desmodur ® XP 2679 Aliphatic polyisocyanate (HDI allophanate trimer) Desmodur ® XP 2714 Silane-functional aliphatic polyisocyanate based on hexamethylene diisocyanate Desmodur ® XP 2730 Low-viscosity, aliphatic polyisocyanate (HDI uretdione) Desmodur ® XP 2731 Aliphatic polyisocyanate (HDI allophanate trimer) Desmodur ® XP 2742 Modified aliphatic Polyisocyanate (HDI-Trimer), contains SiO2 - nanoparticles

Additional isocyanates suitable for certain embodiments of the present invention are sold under the trade name Tolonate® (Perstorp). In certain embodiments, the isocyanates are selected from the group consisting of the materials shown in Table 3, and typically from the subset of this list that are between 1.95 and 2.1 functional isocyanates:

TABLE 3 Tolonate ™ D2 a blocked aliphatic polyisocyanate, supplied at 75% solids in aromatic solvent Tolonate ™ HDB a viscous solvent-free aliphatic polyisocyanate Tolonate ™ HDB-LV a solvent free low viscosity aliphatic polyisocyanate Tolonate ™ HDB 75 B an aliphatic polyisocyanate, supplied at 75% solids in methoxy propyl acetate Tolonate ™ HDB 75 BX an aliphatic polyisocyanate, supplied at 75% solids Tolonate ™ HDT a medium viscosity, solvent-free aliphatic polyisocyanate Tolonate ™ HDT-LV is a solvent free low viscosity aliphatic polyisocyanate Tolonate ™ HDT-LV2 a solvent free, very low viscosity aliphatic polyisocyanate Tolonate ™ HDT 90 an aliphatic polyisocyanate, based on HDI- trimer (isocyanurate), supplied at 90% solids Tolonate ™ HDT 90 B an aliphatic polyisocyanate, based on HDI- trimer (isocyanurate), supplied at 90% solids Tolonate ™ IDT 70 B an aliphatic polyisocyanate, based on HDI- trimer (isocyanurate), supplied at 70% solids Tolonate ™ IDT 70 S an aliphatic polyisocyanate, based on HDI- trimer (isocyanurate), supplied at 70% solids Tolonate ™ X FD 90 B a high functionality, fast drying aliphatic polyisocyanate based on HDI-trimer, supplied at 90% solids

Other isocyanates suitable for certain embodiments of the present invention are sold under the trade name Mondur® available from Bayer Material Science. In certain embodiments, the isocyanates are selected from the group consisting of the materials shown in Table 4, and typically from the subset of this list that are between 1.95 and 2.1 functional isocyanates:

TABLE 4 Trade Name Description MONDUR 445 TDI/MDI blend polyisocyanate; blend of toluene diisocyanate and polymeric diphenylmethane diisocyanate; NCO weight 44.5-45.2% MONDUR 448 modified polymeric diphenylmethane diisocyanate (pMDI) prepolymer; NCO weight 27.7%; viscosity 140 mPa · s @ 25° C.; equivalent weight 152; functionality 2.2 MONDUR 489 modified polymeric diphenylmethane diisocyanate (pMDI); NCO weight 31.5%; viscosity 700 mPa · s @ 25° C.; equivalent weight 133; functionality 3.0 MONDUR 501 modified monomeric diphenylmethane diisocyanate (mMDI); isocyanate-terminated polyester prepolymer; NCO weight 19.0%; viscosity 1,100 mPa · s @ 25° C.; equivalent weight 221; functionality 2 MONDUR 541 polymeric diphenylmethane diisocyanate (pMDI); binder for composite wood products and as a raw material in adhesive formulations; NCO weight 31.5%; viscosity 200 mPa · s @ 25° C. MONDUR 582 polymeric diphenylmethane diisocyanate (pMDI); binder for composite wood products and as a raw material in adhesive formulations; NCO weight 31.0%; viscosity 200 mPa · s @ 25° C. MONDUR 541-Light polymeric diphenylmethane diisocyanate (pMDI); NCO weight 32.0%; viscosity 70 mPa · s @ 25° C.; equivalent weight 131; functionality 2.5 MONDUR 841 modified polymeric MDI prepolymer; NCO, Wt 30.5%; Acidity, Wt 0.02%; Amine Equivalent 132; Viscosity at 25° C., mPa · s 350; Specific gravity at 25° C. 1.24; Flash Point, PMCC, ° F. > 200 MONDUR 1437 modified diphenylmethane diisocyanate (mMDI); isocyanate-terminated polyether prepolymer; NCO weight 10.0%; viscosity 2,500 mPa · s @ 25° C.; equivalent weight 420; functionality 2 MONDUR 1453 modified diphenylmethane diisocyanate (mMDI); isocyanate-terminated polyether prepolymer based on polypropylene ether glycol (PPG); NCO weight 16.5%; viscosity 600 mPa · s @ 25° C.; equivalent weight 254; functionality 2 MONDUR 1515 modified polymeric diphenylmethane diisocyanate (pMDI) prepolymer; used in the production of rigid polyurethane foams, especially for the appliance industry; NCO weight 30.5%; viscosity 350 mPa · s @ 25° C. MONDUR 1522 modified monomeric 4,4-diphenylmethane diisocyanate (mMDI); NCO weight 29.5%; viscosity 50 mPa · s @ 25° C.; equivalent weight 143; functionality 2.2 MONDUR MA-2300 modified monomeric MDI, allophanate-modified 4,4′-diphenylmethane diisocyanate (mMDI); NCO weight 23.0%; viscosity 450 mPa · s @ 25° C.; equivalent weight 183; functionality 2.0 MONDUR MA 2600 modified monomeric MDI, allophanate-modified 4,4′-diphenylmethane diisocyanate (mMDI); NCO weight 26.0%; viscosity 100 mPa · s @ 25° C.; equivalent weight 162; functionality 2.0 MONDUR MA 2601 aromatic diisocyanate blend, allophanate-modified 4,4′-diphenylmethane diisocyanate (MDI) blended with polymeric diphenylmethane diisocyanate (pMDI) containing 2,4′-isomer; NCO weight 29.0%; viscosity 60 mPa · s @ 25° C.; equivalent weight 145; functionality 2.2 MONDUR MA 2603 MDI prepolymer; isocyanate-terminated (MDI) prepolymer blended with an allophanate-modified 4,4′-diphenylmethane diisocyanate (MDI); NCO weight 16.0%; viscosity 1,050 mPa · s @ 25° C.; equivalent weight 263; functionality 2.0 MONDUR MA-2902 modified monomeric MDI, allophanate-modified 4,4′-diphenylmethane diisocyanate (mMDI); NCO weight 29.0%; viscosity 40 mPa · s @ 25° C.; equivalent weight 145; functionality 2.0 MONDUR MA-2903 modified monomeric MDI; isocyanate-terminated (MDI) prepolymer; NCO weight 19.0%; viscosity 400 mPa · s @ 25° C.; equivalent weight 221; functionality 2.0 MONDUR MA-2904 Allophanate-modified MDI polyether prepolymer; NCO weight 12.0%; viscosity 1,800 mPa · s @ 25° C.; equivalent weight 350; functionality of 2.0 MONDUR MB high-purity grade difunctional isocyanante, diphenylmethane 4,4′-diiscocyanate; used in production of polyurethane elastomers, adhesives, coatings and intermediate polyurethane products; appearance colorless solid or liquid; specific gravity @ 50° C. ± 15.5 1.19; flash point 202° C. PMCC; viscosity (in molten form) 4.1 mPa · S; bult density 10 lb/gal (fused) or 9.93 lb/gal (molten); freezing temperature 39° C. MONDUR MLQ monomeric diphenylmethan diisocyanate; used in a foams, cast elastomers, coatings and ahdesives; appearance light yellow clear liquid, NCO 33.4% wt; 1.19 specific gravity at 25° C., 196° C. flash point, DIN 51758; 11-15° C. freezing temperature MONDUR MQ high-purity-grade difunctional isocyanate, diphenylmethane 4,4′-diisocyanate (MDI); used in production of solid polyurethane elastomers, adhesives, coatings and in intermediate polyurethane products; appearance colorless solid or liquid; specific gravity 1.19 @ 50° C.; flash point 202° C. PMCC; viscosity 4.1 mPa · S; bulk density 10 lb./gal (fused) or 9.93 lb./gal (molten); freezing temperature 39° C. MONDUR MR polymeric diphenylmethane diisocyanate (pMDI); NCO weight 31.5%; viscosity 200 mPa · s @ 25° C.; equivalent weight 133; functionality 2.8 MONDUR MR LIGHT polymeric diphenylmethane diisocyanate (pMDI); NCO weight 31.5%; viscosity 200 mPa · s @ 25° C.; equivalent weight 133; functionality 2.8 MONDUR MR-5 polymeric diphenylmethane diisocyanate (pMDI); NCO weight 32.5%; viscosity 50 mPa · s @ 25° C.; equivalent weight 129; functionality 2.4 MONDUR MRS 2,4′ rich polymeric diphenylmethane diisocyanate (pMDI); NCO weight 31.5%; viscosity 200 mPa · s @ 25° C.; equivalent weight 133; functionality2.6 MONDUR MRS 2 2,4′ rich polymeric diphenylmethane diisocyanate (pMDI); NCO weight 33.0%; viscosity 25 mPa · s @ 25° C.; equivalent weight 127; functionality2.2 MONDUR MRS-4 2,4′ rich polymeric diphenylmethane diisocyanate (pMDI); NCO weight 32.5%; viscosity 40 mPa · s @ 25° C.; equivalent weight 129; functionality 2.4 MONDUR MRS-5 2,4′ rich polymeric diphenylmethane diisocyanate (pMDI); NCO weight 32.3%; viscosity 55 mPa · s @ 25° C.; equivalent weight 130; functionality 2.4 MONDUR PC modified 4,4′ diphenylmethane diisocyanate (mMDI); NCO weight 25.8%; viscosity 145 mPa · s @ 25° C.; equivalent weight 163; functionality 2.1 MONDUR PF modified 4,4′ diphenylmethane diisocyanate (mMDI) prepolymer; NCO weight 22.9%; viscosity 650 mPa · s @ 25° C.; equivalent weight 183; functionality 2 MONDUR TD-65 monomeric toluene diisocyanate (TDI); 65/35 mixture of 2,4 and 2.6 TDI; NCO weight 48%; viscosity 3 mPa · s @ 25° C.; equivalent weight 87.5; functionality 2 MONDUR TD-80 GRADE monomeric toluene diisocyanate (TDI); 80/20 mixture of the 2,4 and 2,6 isomer; A NCO weight 48%; viscosity 5 mPa · s @ 25° C.; equivalent weight 87.5; functionality 2 MONDURTD-80 GRADE monomeric toluene diisocyanate (TDI); 80/20 mixture of the 2,4 and 2,6 isomer; A/GRADE B NCO weight 48%; viscosity 5 mPa · s @ 25° C.; equivalent weight 87.5; functionality 2

In certain embodiments, one or more of the above-described isocyanate compositions is provided in a formulation typical of a mixture known in the art of polyurethane adhesives manufacture. Such mixtures may comprise prepolymers formed by the reaction of a molar excess of one or more isocyanates with reactive molecules comprising reactive functional groups such as alcohols, amines, thiols, carboxylates and the like. These mixtures may also comprise solvents, surfactants, stabilizers, and other additives known in the art.

In certain embodiments, the composition of the adhesive might comprise a blocked isocyante. Such mixtures do not react under normal conditions, even in the presence of water. Instead curing is triggered by heating.

III. PRE-POLYMERS

In another aspect, the present invention encompasses prepolymers comprising isocyanate-terminated epoxide CO₂-derived polyols. In certain embodiments, such isocyanate-terminated prepolymers comprise a plurality of epoxide-CO₂-derived polyol segments linked via urethane bonds formed from reaction with polyisocyanate compounds.

In certain embodiments, a prepolymer of the present invention is the result of a reaction between one or more of the aliphatic polycarbonate polyols described above with a stoichiometric excess of any one or more of the diisocyanates described herein. The degree of polymerization of these prepolymers (i.e. the average number of polyol segments contained in the prepolymer chains) can be manipulated by controlling the relative amount of isocyanate, as well as the order of reagent addition and the reaction conditions.

In certain embodiments, prepolymers comprise compounds conforming to a formula:

where, the black rectangles

represent the carbon skeleton of the diisocyanate, R¹, R², R³, R⁴, n, x, and y, are as defined above and in the classes and subclasses herein.

In certain embodiments, prepolymers comprise compounds conforming to a formula:

wherein Q is 0 or an integer between 1 and about 50, each open rectangle,

, represents a polyol moiety each of which may be the same or different, and

, is as defined above and in the classes and subclasses herein. In certain of these embodiments, some of the polyol moieties are derived from one or more of the aliphatic polycarbonate polyols as defined herein, while other of the polyol moieties may be derived from other polyols such as polyether or polyester polyols as described herein.

In certain embodiments, prepolymers comprise chains conforming to the formula:

wherein,

, {circle around (Z)}, Q, R², R⁴, and n, are as defined above and in the classes and subclasses herein.

In other embodiments, a prepolymer may be formed by reacting a stoichiometric excess of polyol with a limited amount of isocyanate. In such embodiments, the inventive prepolymer has —OH end groups and contains two or more polyol units connected by urethane linkages. In certain embodiments, such prepolymers conform to a structure:

wherein

,

, and Q, are as defined above and in the classes and subclasses herein.

In certain embodiments, such prepolymers have structures conforming to:

wherein,

,

, {circle around (Z)}, Q, R¹, R², R³, R⁴, and n, are as defined above and in the classes and subclasses herein.

IV. OTHER CO-REACTANTS AND ADDITIVES

As described above, in some embodiments, compositions of the present invention can include one or more of the aliphatic polycarbonate polyols described in Section I above. Additional aliphatic polycarbonate polyols suitable for the formulation of such mixtures of the present invention are disclosed in WO 2010/028362.

In certain embodiments, these mixtures comprise the aliphatic polycarbonate polyols in combination with one or more additional polyols and/or one or more additives. In certain embodiments, the additional polyols are selected from the group consisting of: polyester polyols, in some cases based on adipic acid and various diols; polyether polyols; and/or polycaprolactone polyols. In certain embodiments, the mixtures comprise additional reactive small molecules known as chain extenders such as amines, alcohols, thiols or carboxylic acids that participate in bond-forming reactions with isocyanates. In certain embodiments, additives are selected from the group consisting of: solvents, fillers, clays, blocking agents, stabilizers, thixotropes, plasticizers, compatibilizers, colorants, UV stabilizers, flame retardants, and the like.

A. Additional Polyols

In certain embodiments, the mixtures of the present invention comprise aliphatic polycarbonate polyols as described above in combination with one or more additional polyols such as are traditionally used in polyurethane adhesive compositions. In embodiments where additional polyols are present, they may comprise up to about 95 weight percent of the total polyol content with the balance of the polyol mixture made up of one or more aliphatic polycarbonate polyols described in Section I above and in the examples and specific embodiments herein.

In embodiments where mixtures of the present invention comprise or derived from a mixture of one or more aliphatic polycarbonate polyols and one or more additional polyols, the additional polyols are selected from the group consisting of polyether polyols, polyester polyols, polystyrene polyols, polyether-carbonate polyols, polyether-ester carbonates, butane diol adipate polyols, ethylene glocol adipate polyols, hexane diol adipate polyols, polycaprolactone polyols, polycarbonate polyols, polytetramethylene ether glycol (PTMEG) polyols, EO/PO polyether polyols, and mixtures of any two or more of these. In certain embodiments, mixtures of the present invention comprise or derived from a mixture of one or more aliphatic polycarbonate polyols as described herein and one or more other polyols selected from the group consisting of materials available commercially under the trade names: Voranol® (Dow), SpecFlex® (Dow), Tercarol® (Dow), Caradol® (Shell), Hyperliter®, Acclaim® (Bayer Material Science), Ultracel® (Bayer Material Science), Desmophen® (Bayer Material Science), Arcol® (Bayer Material Science), Stepanpol® (Stepan), Terate® (Invista), Terol® (oxid), Agrol® (BioBased Technologies), BiOH® (Cargil), HB® (Honey Bee), Polycin® (Vertellus), Poly-BD® (Cray Valley) and Krasol® (Cray Valley).

In certain embodiments, the mixtures of the present invention contain polyether polyols, polyester polyols, and/or polycaprolactone polyols in combination with one or more aliphatic polycarbonate polyols as described herein. In certain embodiments, such polyols are characterized in that they have an Mn between about 500 and about 10,000 g/mol. In certain embodiments, such polyols have an Mn between about 500 and about 5,000 g/mol. In certain embodiments, such polyols have an Mn between about 1,500 and about 25,000 g/mol.

In certain embodiments, mixtures of the present invention contain polyether polyols, polyester polyols, and/or polycaprolactone polyols in combination with one or more aliphatic polycarbonate polyols as described herein. In certain embodiments, such polyols are characterized in that they have a functionality between 1.9 and 2.5. In certain embodiments, such polyols are characterized in that they have a functionality between 1.95 and 2.2. In certain embodiments, such polyols have a functionality greater than 2.5, in which cases such high-functionality polyols typically compromise a minority of the overall polyol formulation. Polyester polyols that may be present include those which can be obtained by known methods, for example, polyester polyols can be based on the reaction of adipic acid or succinic acid (or their corresponding reactive derivatives or anhydrides) with various diols including, butanediol (BDO), hexanediol (HDO), and ethylene glycol (EG), propane diol (PDO).

Polyether polyols that may be present include those which can be obtained by known methods, for example, polyether polyols can be produced by anionic polymerization with alkali hydroxides such as sodium hydroxide or potassium hydroxide or alkali alcoholates, such as sodium methylate, sodium ethylate, or potassium ethylate or potassium isopropylate as catalysts and with the addition of at least one initiator molecule containing 2 to 8, preferably 2, reactive hydrogens or by cationic polymerization with Lewis acids such as antimony pentachloride, boron trifluoride etherate, etc., or bleaching earth as catalysts from one or more alkylene oxides with 2 to 4 carbons in the alkylene radical. Any suitable alkylene oxide may be used such as 1,3-propylene oxide, 1,2- and 2,3 butylene oxide, amylene oxides, styrene oxide, and preferably ethylene oxide and 1,2-propylene oxide and mixtures of these oxides. The polyalkylene polyether polyols may be prepared from other starting materials such as tetrahydrofuran and alkylene oxide-tetrahydrofuran mixtures; epihalohydrins such as epichlorohydrin; as well as aralkylene oxides such as styrene oxide. The polyalkylene polyether polyols may have either primary or secondary hydroxyl groups, preferably secondary hydroxyl groups from the addition of propylene oxide onto an initiator because these groups are slower to react. Included among the polyether polyols are polyoxyethylene glycol, polyoxypropylene glycol, polyoxybutylene glycol, polytetramethylene glycol, block copolymers, for example, combinations of polyoxypropylene and polyoxyethylene glycols, poly-1,2-oxybutylene and polyoxyethylene glycols, poly-1,4-tetramefhylene and polyoxyethylene glycols, and copolymer glycols prepared from blends or sequential addition of two or more alkylene oxides. The polyalkylene polyether polyols may be prepared by any known process such as, for example, the process disclosed by Wurtz in Encyclopedia of Chemical Technology, Vol. 7, pp. 257-262, published by Interscience Publishers, Inc. (1951) or in U.S. Pat. No. 1,922,459. Polyethers which are preferred include the alkylene oxide addition products of polyhydric alcohols such as ethylene glycol, propylene glycol, dipropylene glycol, trimethylene glycol, 1,2-butanediol, 1,5-pentanediol, 1,6hexanediol, 1,7-heptanediol, hydroquinone, resorcinol glycerol, glycerine, 1,1,1-trimethylol-propane, 1,1,1trimethylolethane, pentaerythritol, 1,2,6-hexanetriol, a-methyl glucoside, sucrose, and sorbitol. Also included within the term “polyhydric alcohol” are compounds derived from phenol such as 2,2-bis(4-hydroxyphenyl)-propane, commonly known as Bisphenol A. Suitable organic amine initiators which may be condensed with alkylene oxides include aromatic amines-such as aniline, N-alkylphenylene-diamines, 2,4′-, 2,2′-, and 4,4′-methylenedianiline, 2,6- or 2,4-toluenediamine, vicinal toluenediamines, o-chloroaniline, p-aminoaniline, 1,5-diaminonaphthalene, methylene dianiline, the various condensation products of aniline and formaldehyde, and the isomeric diaminotoluenes; and aliphatic amines such as mono-, di-, and trialkanolamines, ethylene diamine, propylene diamine, diethylenetriamine, methylamine, triisopropanolamine, 1,3-diaminopropane, 1,3-diaminobutane, and 1,4-diaminobutane. Preferable amines include monoethanolamine, vicinal toluenediamines, ethylenediamines, and propylenediamine Yet another class of aromatic polyether polyols contemplated for use in this invention are the Mannich-based polyol an alkylene oxide adduct of phenol/formaldehyde/alkanolamine resin, frequently called a “Mannich” polyol such as disclosed in U.S. Pat. Nos. 4,883,826; 4,939,182; and 5,120, 815. In certain embodiments where additional polyols are present, they comprise from about 5 weight percent to about 95 weight percent of the total polyol content with the balance of the polyol mixture made up of one or more aliphatic polycarbonate polyols described in Section I above and in the examples and specific embodiments herein. In certain embodiments, up to about 75 weight percent of the total polyol content of the mixture is aliphatic polycarbonate polyol. In certain embodiments, up to about 50 weight percent of the total polyol content of the mixture is aliphatic polycarbonate polyol. In certain embodiments, up to about 40 weight percent, up to about 30 weight percent, up to about 25 weight percent, up to about 20 weight percent, up to about 15 weight percent, or up to about 10 weight percent of the total polyol content of the mixture is aliphatic polycarbonate polyol. In certain embodiments, at least about 5 weight percent of the total polyol content of the mixture is aliphatic polycarbonate polyol. In certain embodiments, at least about 10 weight percent of the total polyol content of the mixture is aliphatic polycarbonate polyol. In certain embodiments, at least about 15 weight percent, at least about 20 weight percent, at least about 25 weight percent, at least about 40 weight percent, or at least about 50 weight percent, of the total polyol content of the mixture is aliphatic polycarbonate polyol.

B. Chain Extenders

In certain embodiments, the mixtures of the present invention include one or more small molecules reactive toward isocyanates. In certain embodiments, reactive small molecules included in the inventive mixtures comprise low molecular weight organic molecules having one or more functional groups selected from the group consisting of alcohols, amines, carboxylic acids, thiols, and combinations of any two or more of these.

In certain embodiments, the mixtures of the present invention include one or more alcohols. In certain embodiments, the mixtures include polyhydric alcohols.

In certain embodiments, reactive small molecules included in the inventive mixtures comprise dihydric alcohols. In certain embodiments, the dihydric alcohol comprises a C₂₋₄₀ diol. The polyol compound is selected from aliphatic and cycloaliphatic polyol compounds, for example, ethylene glycol, 1,2-ethanediol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,2-propylene glycol, 1,3-butane diol, 1,4-butane diol, 1,5-pentane diol, 1,6-hexane diol, 1,8-octane diol, 1,9-nonane diol, 1,10-decane diol, neopentyl glycol, 3-methyl-1,5-pentane diol, 3,3-dimethylolheptane, 1,4-cyclohexane diol, 1,4-cyclohexanedimethanol and 1,4-dihydroxyethyl cyclohexane; and aliphatic and aromatic polyamine compounds, for example, ethylene diamine, 1,2-propylene diamine, 1,6-hexamethylene diamine, isophorone diamine bis(4-aminocyclohexyl)methane, piperazine and meta- or para-xylene diamine; aliphatic, cycloaliphatic and aromatic aminoalcohol compounds, for example, 2-ethanolamine, N-methyldiethanolamine, N-phenyldipropanolamine; hydroxyalkyl sulfamides, for example, hydroxyethyl sulfamide and hydroxyethylaminoethyl sulfamide; urea and water. Among the above-mentioned chain extending compounds, preferably 1,4-butane diol, 2-ethanolamine, and 1,2-propylenediamine are employed. In certain embodiments, the chain extender is selected from the group consisting of: 1,4-cyclohexanediethanol, isosorbide, glycerol monoesters, glycerol monoethers, trimethylolpropane monoesters, trimethylolpropane monoethers, pentaerythritol diesters, pentaerythritol diethers, and alkoxylated derivatives of any of these. The above-mentioned chain-extending compounds may be used alone or in a mixture of two or more thereof.

In certain embodiments, a reactive small molecule included in the inventive mixtures comprises a dihydric alcohol selected from the group consisting of: diethylene glycol, triethylene glycol, tetraethylene glycol, higher poly(ethylene glycol), such as those having number average molecular weights of from 220 to about 2000 g/mol, dipropylene glycol, tripropylene glycol, and higher poly(propylene glycols) such as those having number average molecular weights of from 234 to about 2000 g/mol.

In certain embodiments, a reactive small molecule included in the inventive mixtures comprises an alkoxylated derivative of a compound selected from the group consisting of: a diacid, a diol, or a hydroxy acid. In certain embodiments, the alkoxylated derivatives comprise ethoxylated or propoxylated compounds.

In certain embodiments, a reactive small molecule included in the inventive mixtures comprises a polymeric diol. In certain embodiments, a polymeric diol is selected from the group consisting of polyethers, polyesters, hydroxy-terminated polyolefins, polyether-copolyesters, polyether polycarbonates, polycarbonate-copolyesters, and alkoxylated analogs of any of these. In certain embodiments, the polymeric diol has an average molecular weight less than about 2000 g/mol.

In certain embodiments, a reactive small molecule comprises a hydroxy-carboxylic acid having the general formula (HO)_(x)Q(COOH)_(y), wherein Q is a straight or branched hydrocarbon radical containing 1 to 12 carbon atoms, and x and y are each integers from 1 to 3. In certain embodiments, a coreactant comprises a diol carboxylic acid. In certain embodiments, a coreactant comprises a bis(hydroxylalkyl) alkanoic acid. In certain embodiments, a coreactant comprises a bis(hydroxylmethyl) alkanoic acid. In certain embodiments the diol carboxylic acid is selected from the group consisting of 2,2 bis-(hydroxymethyl)-propanoic acid (dimethylolpropionic acid, DMPA) 2,2-bis(hydroxymethyl) butanoic acid (dimethylolbutanoic acid; DMBA), dihydroxysuccinic acid (tartaric acid), and 4,4′-bis(hydroxyphenyl) valeric acid. In certain embodiments, a coreactant comprises an N,N-bis(2-hydroxyalkyl)carboxylic acid.

In certain embodiments, a reactive small molecule comprises a polyhydric alcohol comprising one or more amino groups. In certain embodiments, a reactive small molecule comprises an amino diol. In certain embodiments, a reactive small molecule comprises a diol containing a tertiary amino group. In certain embodiments, an amino diol is selected from the group consisting of: diethanolamine (DEA), N-methyldiethanolamine (MDEA), N-ethyldiethanolamine (EDEA), N-butyldiethanolamine (BDEA), N,N-bis(hydroxyethyl)-a-amino pyridine, dipropanolamine, diisopropanolamine (DIPA), N-methyldiisopropanolamine, Diisopropanol-p-toluidine, N,N-Bis(hydroxyethyl)-3-chloroaniline, 3-diethylaminopropane-1,2-diol, 3-dimethylaminopropane-1,2-diol and N-hydroxyethylpiperidine. In certain embodiments, a coreactant comprises a diol containing a quaternary amino group. In certain embodiments, a coreactant comprising a quaternary amino group is an acid salt or quaternized derivative of any of the amino alcohols described above.

In certain embodiments, a reactive small molecule is selected from the group consisting of: inorganic or organic polyamines having an average of about 2 or more primary and/or secondary amine groups, polyalcohols, ureas, and combinations of any two or more of these. In certain embodiments, a reactive small molecule is selected from the group consisting of: diethylene triamine (DETA), ethylene diamine (EDA), meta-xylylenediamine (MXDA), aminoethyl ethanolamine (AEEA), 2-methyl pentane diamine, and the like, and mixtures thereof. Also suitable for practice in the present invention are propylene diamine, butylene diamine, hexamethylene diamine, cyclohexylene diamine, phenylene diamine, tolylene diamine, 3,3-dichlorobenzidene, 4,4′-methylene-bis-(2-chloroaniline), 3,3-dichloro-4,4-diamino diphenylmethane, and sulfonated primary and/or secondary amines. In certain embodiments, reactive small molecule is selected from the group consisting of: hydrazine, substituted hydrazines, hydrazine reaction products, and the like, and mixtures thereof. In certain embodiments, a reactive small molecule is a polyalcohol including those having from 2 to 12 carbon atoms, preferably from 2 to 8 carbon atoms, such as ethylene glycol, diethylene glycol, neopentyl glycol, butanediols, hexanediol, and the like, and mixtures thereof. Suitable ureas include urea and its derivatives, and the like, and mixtures thereof

In certain embodiments, reactive small molecules containing at least one basic nitrogen atom are selected from the group consisting of: mono-, bis- or polyalkoxylated aliphatic, cycloaliphatic, aromatic or heterocyclic primary amines, N-methyl diethanolamine, N-ethyl diethanolamine, N-propyl diethanolamine, N-isopropyl diethanolamine, N-butyl diethanolamine, N-isobutyl diethanolamine, N-oleyl diethanolamine, N-stearyl diethanolamine, ethoxylated coconut oil fatty amine, N-allyl diethanolamine, N-methyl diisopropanolamine, N-ethyl diisopropanolamine, N-propyl diisopropanolamine, N-butyl diisopropanolamine, cyclohexyl diisopropanolamine, N,N-diethoxylaniline, N,N-diethoxyl toluidine, N,N-diethoxyl-1-aminopyridine, N,N′-diethoxyl piperazine, dimethyl-bis-ethoxyl hydrazine, N,N′-bis-(2-hydroxyethyl)-N,N′-diethylhexahydr op-phenylenediamine, N-12-hydroxyethyl piperazine, polyalkoxylated amines, propoxylated methyl diethanolamine, N-methyl-N,N-bis-3-aminopropylamine, N-(3-aminopropyl)-N,N′-dimethyl ethylenediamine, N-(3-aminopropyl)-N-methyl ethanolamine, N,N′-bis-(3-aminopropyl)-N,N′-dimethyl ethylenediamine, N,N′-bis-(3-aminopropyl)-piperazine, N-(2-aminoethyl)-piperazine, N,N′-bisoxyethyl propylenediamine, 2,6-diaminopyridine, diethanolaminoacetamide, diethanolamidopropionamide, N,N-bisoxyethylphenyl thiosemicarbazide, N,N-bis-oxyethylmethyl semicarbazide, p,p′-bis-aminomethyl dibenzyl methylamine, 2,6-diaminopyridine, 2-dimethylaminomethyl-2-methylpropanel, 3-diol. In certain embodiments, chain-extending agents are compounds that contain two amino groups. In certain embodiments, chain-extending agents are selected from the group consisting of: ethylene diamine, 1,6-hexamethylene diamine, and 1,5-diamino-1-methyl-pentane.

C. Catalysts

In certain embodiments, no catalysts are used in the mixtures. In certain embodiments, in the polymerization reaction for the polyurethane, a conventional catalyst comprising an amine compound or tin compound can be employed to promote the reaction. These embodiments are most commonly found in reactive extrusion methods of polyurethane adhesive production. Any suitable urethane catalyst may be used, including tertiary amine compounds and organometallic compounds may be used. Exemplary tertiary amine compounds include triethylenediamine, N-methylmorpholine, N,N-dimethylcyclohexylamine, pentamethyldiethylenetriamine, tetramefhylefhylenediamine, 1-methyl-4-dimethylaminoethylpiperazine, 3-methoxy-N-dimethylpropylamine, N-ethylmorpholine, diethylethanolamine, N-cocomorpholine, N,N-dimefhyl-N′,N′-dimethyl isopropylpropylenediamine, N,N-diethyl-3-diethylaminopropylamine and dimethylbenzylamine Exemplary organometallic catalysts include organomercury, organolead, organoferric and organotin catalysts, with organotin catalysts being preferred among these. Suitable tin catalysts include stannous chloride, tin salts of carboxylic acids such as dibutyltin dilaurate, as well as other organometallic compounds such as are disclosed in U.S. Pat. No. 2,846,408. A catalyst for the trimerization of polyisocyanates, resulting in a polyisocyanurate, such as an alkali metal alkoxide may also optionally be employed herein. Such catalysts are used in an amount which measurably increases the rate of polyurethane or polyisocyanurate formation.

In certain embodiments, where mixtures of the present invention comprise catalysts, the catalysts comprise tin based materials. In certain embodiments, tin catalysts are selected from the group consisting of: di-butyl tin dilaurate, dibutylbis(laurylthio)stannate, dibutyltinbis(isooctylmercapto acetate) and dibutyltinbis(isooctylmaleate), tin octanoate and mixtures of any two or more of these.

In certain embodiments, catalysts included in the mixtures comprise tertiary amines. In certain embodiments, catalysts included in the mixtures are selected from the group consisting of: DABCO, pentametyldipropylenetriamine, bis(dimethylamino ethyl ether), pentamethyldiethylenetriamine, DBU phenol salt, dimethylcyclohexylamine, 2,4,6-tris(N,N-dimethylaminomethyl)phenol (DMT-30), triazabicyclodecene (TBD), N-methyl TBD, 1,3,5-tris(3-dimethylaminopropyl)hexahydro-s-triazine, ammonium salts and combinations or formulations of any of these.

Typical amounts of catalyst are 0.001 to 10 parts of catalyst per 100 parts by weight of total polyol in the mixture. In certain embodiments, catalyst levels in the formulation, when used, range between about 0.001 pph (weight parts per hundred) and about 3 pph based on the amount of polyol present in the mixture. In certain embodiments, catalyst levels range between about 0.05 pph and about 1 pph, or between about 0.1 pph and about 0.5 pph.

D. Mono-Functional Materials

In certain embodiments, monofunctional components are added. Suitable monofunctional components can include molecules having a single isocyanate-reactive functional group such as an alcohol, amine, carboxylic acid, or thiol. A monofunctional component will serve as a chain termination which can be used to limit molecular weight or crosslinking if higher functionality species are used. U.S. Pat. No. 5,545,706 illustrates the use of a monofunctional alcohol in a substantially linear polyurethane formulation. The monofunctional alcohol can be any compound with one alcohol available for reaction with isocyanate such as methanol, ethanol, propanol, isopropanol, butanol, isobutanol, pentanol, hexanol, heptanol, octanol, nonanol, decanol, dodecanol, phenol and the like. Additionally, the monofunctional component can be added as a low molecular weight polymer that has been initiated by or reacted with the monofunctional alcohol. The monofunctional alcohol can be a polyether such as polypropylene oxide or polyethylene oxide initiated with any of the monofunctional alcohols listed. The monofunctional alcohol can be a polyester polymer where the monofunctional alcohol is added to the recipe. The monofunctional alcohol can be a polycarbonate polymer such as polyethylene carbonate or polypropylene carbonate initiated with a monofunctional anion, such as halide, nitrate, azide, carboxylate, or a monohydric alcohol.

Similarly, the monofunctional component could be an isocyanate. Any monofunctional isocyanate could be added for this same function. Possible materials include phenyl isocyanate, naphthyl isocyanate, methyl isocyanate, ethyl isocyanate, propyl isocyanate, butyl isocyanate, hexyl isocyanate, octyl isocyanate and the like.

E. Additives

In addition to the above components, mixtures of the present invention may optionally contain various additives as are known in the art of polyurethane adhesive technology. Such additives may include, but are not limited to solvents, fillers, clays, blocking agents, stabilizers, thixotropes, plasticizers, compatibilizers, colorants, UV stabilizers, flame retardants, and the like.

1. Solvents

If desired, the polyurethane adhesives or pre-polymers can be dispersed in a solvent which can include water or organic solvents known to those skilled in the art. Suitable solvents can include aliphatic, aromatic, or halogenated hydrocarbons, ethers, esters, ketones, lactones, sulfones, nitriles, amides, nitromethane, propylene carbonate, dimethyl carbonate and the like. Representative examples include, but are not limited to: acetone, acetonitrile, benzene, butanol, butyl acetate, g-butyrolactone, butyl caribitl acetate, carbitol acetate, chloroform, cyclohexane, 1,2-dichloromethane, dibasic ester, diglyme, 1,2-dimethoxyethane, dimethylacetamide, dimethylsulfoxide, dimethformamide, 1,4-dioxane, ethanol, ethyl acetate, ethyl ether, ethylene, glycol, hexane, hydroxylmethyl methacrylate, isopropyl acetate, methanol, methyl acetate, methyl amyl ketone, methyl isobutyl ketone, methylene chloride, methyl ethyl ketone, monoglyme, methyl methacrylate, propylene carbobonate, propylene oxide, styrene, alpha-terpineol, tetrahydrofuran, texanol, toluene, diethyl succinate, diethylene glycol methyl ether, ethylene glycol diacetate, triethyl phosphate and the like.

2. Fillers

Optional components of the adhesive of the invention include fillers. Such fillers are well known to those skilled in the art and include carbon black, titanium dioxide, calcium carbonate, surface treated silicas, titanium oxide, fume silica, talc, aluminum trihydrate and the like. In certain embodiments, fillers comprise carbon black. In certain embodiments, more than one reinforcing filler may be used, of which one is carbon black and a sufficient amount of carbon black is used to provide the desired black color to the adhesive. In certain embodiments, a reinforcing filler is used in sufficient amount to increase the strength of the adhesive and/or to provide thixotropic properties to the adhesive. The amounts of filler or other additives will vary depending on the desired application.

3. Clays

Among optional materials in the adhesive composition are clays. Preferred clays useful in the invention include kaolin, surface treated kaolin, calcined kaolin, aluminum silicates and surface treated anhydrous aluminum silicates. The clays can be used in any form which facilitates formulation of a pumpable adhesive. Preferably the clay is in the form of pulverized powder, spray-dried beads or finely ground particles.

4. Blocking Agents

One or more blocking agents are utilized to provide an induction period between the mixing of the two parts of the adhesive composition and the initiation of the cure. The addition of the blocking agents provides an induction period which causes a reduction in the curing rate immediately after mixing of the components of the adhesive. The reduction in the curing rate results in lower initial tensile shear strengths and storage moduli immediately after mixing than those found in compositions that do not contain a blocking agent. Following the induction period the adhesive quickly cures so that the tensile shear strength and storage modulus are similar to those produced by adhesives that do not contain the blocking agent. Such thixotropes are well known to those skilled in the art and include hydroxyl containing compounds such as diethylene glycol, mono alkyl ethers, butanone oxime, methyl ethyle ketone oxime, nonylphenol, phenol and cresol; amine containing compounds such as caprolactam, diisopropyl amine, 1,2,4-triazole and 3,5-dimethyl pyrazole; and aliphatic containing compounds such as dialkyl malonate.

5. Stabilizers

An adhesive of this invention may further comprise stabilizers which function to protect the adhesive composition from moisture, thereby inhibiting advancement and preventing premature crosslinking of the isocyanates in the adhesive formulation. Included among such stabilizers are diefhylmalonate and alkylphenol alkylates.

6. Thixotrope

Optionally, the adhesive composition may further comprise a thixotrope. Such thixotropes are well known to those skilled in the art and include alumina, limestone, talc, zinc oxides, sulfur oxides, calcium carbonate, perlite, slate flour, salt (NaCl), cyclodextrin and the like. The thixotrope may be added to the adhesive of composition in a sufficient amount to give the desired rheological properties.

7. Plasticizers

Adhesive compositions of the present invention may further comprise plasticizers so as to modify the rheological properties to a desired consistency. Such materials should be free of water, inert to isocyanate groups and compatible with a polymer. Suitable plasticizers are well known in the art and preferable plasticizers include alkyl phthalates such as dioctylphthalate or dibutylphthalate, partially hydrogenated terpene commercially available as “HB-40”, trioctyl phosphate, epoxy plasticizers, toluene-sulfamide, chloroparaffins, adipic acid esters, castor oil, toluene and alkyl naphthalenes. The amount of plasticizer in the adhesive composition is that amount which gives the desired rheological properties and/or which is sufficient to disperse any catalyst that may be present in the system.

8. Compatibilizers

In certain embodiments, the mixtures of the present invention comprise one or more suitable compatibilizers. Compatibilizers are molecules that allow two or more nonmiscible ingredients to come together and give a homogeneous liquid phase. Many such molecules are known to the polyurethane industry, these include: amides, amines, hydrocarbon oils, phthalates, polybutyleneglycols, and ureas.

9. Colorants

In certain embodiments, the mixtures of the present invention comprise one or more suitable colorants. Typical inorganic coloring agents included titanium dioxide, iron oxides and chromium oxide. Organic pigments originated from the azo/diazo dyes, phthalocyanines and dioxazines, as well as carbon black. Recent advances in the development of polyol-bound colorants are described in:

-   Miley, J. W.; Moore, P. D. “Reactive Polymeric Colorants For     Polyurethane”, Proceedings Of The SPI-26th Annual Technical     Conference; Technomic: Lancaster, Pa., 1981; 83-86. -   Moore, P. D.; Miley, J. W.; Bates, S. H.; “New Uses For Highly     Miscible Liquid Polymeric Colorants In The Manufacture of Colored     Urethane Systems”; Proceedings of the SPI-27th Annual     Technical/Marketing Conference; Technomic: Lancaster, Pa., 1982;     255-261. -   Bates, S. H.; Miley, J. W. “Polyol-Bound Colorants Solve     Polyurethane Color Problems”; Proceedings Of The SPI-30th Annual     Technical/Marketing Conference; Technomic: Lancaster, Pa., 1986;     160-165 -   Vielee, R. C.; Haney, T. V. “Polyurethanes”; In Coloring of     Plastics; Webber, T. G., Ed., Wiley-Interscience: New York, 1979,     191-204.

10. UV Stabilizers

In certain embodiments, the mixtures of the present invention comprise one or more suitable UV stabilizers. Polyurethanes based on aromatic isocyanates will typically turn dark shades of yellow upon aging with exposure to light. A review of polyurethane weathering phenomena is presented in: Davis, A.; Sims, D. Weathering Of Polymers; Applied Science: London, 1983, 222-237. Light protection agents, such as hydroxybenzotriazoles, zinc dibutyl thiocarbamate, 2,6-ditertiary butylcatechol, hydroxybenzophenones, hindered amines and phosphites have been used to improve the light stability of polyurethanes. Color pigments have also been used successfully.

11. Flame Retardants

In certain embodiments, the mixtures of the present invention comprise one or more suitable flame retardants. Flame retardants are often added to reduce flammability. The choice of flame retardant for any specific polyurethane adhesive often depends upon the intended service application of that adhesive and the attendant flammability testing scenario governing that application. Aspects of flammability that may be influenced by additives include the initial ignitability, burning rate and smoke evolution.

The most widely used flame retardants are the chlorinated phosphate esters, chlorinated paraffins and melamine powders. These and many other compositions are available from specialty chemical suppliers. A review of this subject has been given: Kuryla, W. C.; Papa, A. J. Flame Retardancy of Polymeric Materials, Vol. 3; Marcel Dekker: New York, 1975, 1-133.

V. POLYURETHANE ADHESIVE COMPOSITIONS

In another aspect, the present invention encompasses polyurethane adhesives derived from one or more of aliphatic polycarbonate polyol compositions described above and in the specific embodiments and examples disclosed herein. In certain embodiments, the polyurethane adhesive compositions comprise the reaction product of one or more isocyanates and a mixture containing one or more of the aliphatic polycarbonate polyol compositions defined above.

A. Reactive 1-Component Polyurethane Adhesives

In one aspect, the present invention encompasses reactive one-component adhesives. In certain embodiments, such one-component adhesives compositions are derived from a mixture containing one or more of the aliphatic polycarbonate polyol compositions as defined above and in the embodiments and examples herein.

In certain embodiments the one-component adhesives are prepolymers made with one or more aliphatic polycarbonate polyols; these prepolymers typically have low isocyanate values and are produced by reacting an excess of isocyanate with a relatively high molecular weight polyol. These adhesives are typically cured with water which can be added or which is present in the atmosphere or the material being bonded.

In certain embodiments MDI is the preferred isocyanate to react with one or more aliphatic polycarbonate polyols and optionally one or more other polyols as described above. In certain embodiments requiring unique adhesive performance properties, TDI and/or aliphatic isocyanates are used in place of, or in addition to, MDI.

In certain embodiments the one component adhesives comprise 100% solids (e.g. no solvent is present at the time of application). In certain embodiments, the one component adhesives formulations may be dissolved, dispersed, and/or emulsified in a solvent or water to reduce viscosity or otherwise improve the applicability of the one component adhesive in these applications.

In certain embodiments no catalysts are used. In certain embodiments catalysts are included in the formulation to increase the reaction rate of free isocyanate and water.

In certain embodiments, hydroxyethyl acrylate groups may be included in the aliphatic polycarbonate polyol, other polyols, and/or the derivative prepolymers to introduce ultraviolet light curing properties.

In certain embodiments, fatty acid groups and/or other molecules with unsaturation functionality may be included in the aliphatic polycarbonate polyol, other polyols, and/or the derivative prepolymers to enable cross linking via oxidation.

In certain embodiments, the 1-component adhesive mixture forms a final, cured polyurethane adhesive with the following composition:

-   -   1-80 parts by weight of one or more isocyanate components or         pre-polymers based on isocyanate components as described above         and in the specific embodiments and examples herein;     -   20-99 parts by weight of a polyol component or a polyol-based         pre-polymer component, wherein the polyol component comprises         from about 5 weight percent to 100 weight percent of one or more         of the aliphatic polycarbonate polyols described above and in         the specific embodiments and examples herein;     -   0 to 1 parts by weight of one or more catalysts as described         above and in the specific embodiments and examples herein;     -   0 to 20 parts by weight of one or more chain extenders, wherein         the chain extenders molecules are substantially as described         above and in the specific embodiments and examples herein; and     -   0 to 10 parts by weight of one or more additives, wherein the         additives are selected from the group consisting of: fillers,         clays, blocking agents, stabilizers, thixotropic materials,         plasticizers, compatibilizers, colorants, UV stabilizers or         flame retardents as described above and in the specific         embodiments and examples herein.

B. Reactive 2-Component Polyurethane Adhesives

In another aspect, the present invention encompasses reactive two-component adhesive compositions. In certain embodiments, such two-component adhesive compositions are derived from a mixture containing one or more of the aliphatic polycarbonate polyols as defined above and in the embodiments and examples herein.

In certain embodiments the two-component adhesives include prepolymers derived from one or more aliphatic polycarbonate polyols. These prepolymers can be produced with excess isocyanate and/or excess hydroxyl content and are then mixed with one or more of the isocyanates, aliphatic polycarbonate polyols, other polyols, and other components described above.

In certain embodiments, the two-component adhesives are formulated to an isocyanate index range of 90 to 150. In certain embodiments, isocyanate indexes above 100 are used to increase hardness of the adhesive and to improve bonding to substrates, in particular those substrates with hydroxyl groups on their surfaces. In certain embodiments, isocyanate indexes below 100 are used to produce softer and more flexible adhesives.

In certain embodiments MDI is the preferred isocyanate used in the formulation of the two-component adhesives. In certain embodiments TDI is the preferred isocyanate used in the formulation of the two-component adhesives. In certain embodiments these isocyanates have a functionality greater than two, and may be polymeric. In certain embodiments other isocyanates are used, including aliphatic isocyanates in cases where resistance to ultraviolet light is a requirement.

In certain embodiments only a single aliphatic polycarbonate polyol is used in the formulation of the two-component adhesive. In certain embodiments one or more polycarbonate polyols are mixed with one or more additional polyols as described above. In certain embodiments these polyols have molecular weights between 200 and 10,000 grams per mol, preferably between 300 and 5,000 grams per mol.

In certain embodiments, the two-component adhesives are formulated with isocyanates and/and or polyols which are 2.0 functional or lower. In certain embodiments the adhesives are formulated with isocyanates and/or polyols functionality greater than 2.0 (in other words, some degree of branching) to introduce cross-linking in the cured two-component adhesives. In certain embodiments, the total level of crosslinking is relatively high to produce adhesives with high modulus, high hardness, and good tensile, shear stress, and peel strength properties. In certain embodiments, the total level of crosslinking is relatively low to produce adhesives with greater elasticity.

In certain embodiments the two-component adhesives are applied as 100% solids. In certain embodiments, the two component adhesives may be dissolved, dispersed, and/or emulsified in a solvent or water to reduce viscosity or otherwise improve their applicability. In certain embodiments, solvents such as acetone, methyl ethyl ketone, ethylacetate, toluene, or xylene are preferred.

In certain embodiments no fillers are present in the two-component adhesives. In other embodiments calcium carbonate, talc, clays, or the like are added as fillers to control rheology, reduce shrinkage, reduce cost, and/or for other reasons. In certain embodiments the two-component adhesives include thixotropic agents, flow agents, film-forming additives, and/or catalysts to achieve the processing and finished adhesives properties required.

In certain embodiments, the 2-component adhesive mixture forms a final, cured polyurethane adhesive with the following composition:

-   -   10-40 parts by weight of one or more isocyanate components or         pre-polymers based on isocyanate components as described above         and in the specific embodiments and examples herein;     -   60-90 parts by weight of a polyol component or a polyol-based         pre-polymer component, wherein the polyol component comprises         from about 5 weight percent to 100 weight percent of one or more         of the aliphatic polycarbonate polyols described above and in         the specific embodiments and examples herein;     -   0 to 1 parts by weight of one or more catalysts as described         above and in the specific embodiments and examples herein;     -   0 to 20 parts by weight of one or more chain extenders, wherein         the chain extenders molecules are substantially as described         above and in the specific embodiments and examples herein; and     -   0 to 10 parts by weight of one or more additives, wherein the         additives are selected from the group consisting of: fillers,         clays, blocking agents, stabilizers, thixotropic materials,         plasticizers, compatibilizers, colorants, UV stabilizers or         flame retardents as described above and in the specific         embodiments and examples herein.

In certain embodiments, the present invention encompasses adhesives formulated from a polyol blend comprising one or more of the aliphatic polycarbonate polyol as described hereinabove, and one or more commercially available polyester or polyether polyols. In certain embodiments, the aliphatic polycarbonate content of such blends ranges from about 10 to about 90%. Such blends can be formulated to provide a range of hardness or elasticity as shown in FIG. 8. In certain embodiments, the present invention encompasses adhesive compositions derived from a polyol blend comprising about 10%, about 20%, about 30%, about 40%, about 50%, about 60%, about 70%, or about 80% aliphatic polycarbonate polyol with the balance comprising a polyester polyol. In certain embodiments, such blends comprise poly(butylane adipate) glycol as the polyester polyol. In certain embodiments, the present invention encompasses adhesive compositions derived from a polyol blend comprising about 10%, about 20%, about 30%, about 40%, about 50%, about 60%, about 70%, or about 80% aliphatic polycarbonate polyol with the balance comprising a polyether polyol. In certain embodiments, such blends comprise polyethylene glycol, or polypropylene glycol as the polyether polyol component.

C. Hot-Melt Polyurethane Adhesives

In one aspect, the present invention encompasses reactive hot melt adhesives. In certain embodiments, such reactive hot melt adhesive compositions are derived from a mixture containing one or more of the aliphatic polycarbonate polyol compositions as defined above and in the embodiments and examples herein.

In certain embodiments the hot-melt adhesives include prepolymers derived from one or more aliphatic polycarbonate polyols. These prepolymers can be produced with excess isocyanate and/or excess hydroxyl content and are then mixed with one or more of the isocyanates, aliphatic polycarbonate polyols, other polyols, and other components described above. In certain embodiments the molar ratio of isocyanate to polyol is between 1.5:1 and 4:1, preferably between 1.9:1 and 3:1, and often very near 2:1.

In certain embodiments, MDI is the preferred isocyanate to react with one or more aliphatic polyols and possibly one or more other polyols as described above. In certain embodiments requiring unique hot melt adhesive performance properties, TDI and/or aliphatic isocyanates are used in place of or in addition to MDI.

In certain embodiments the reactive hot melt adhesive prepolymers are produced by reacting an excess of isocyanate with a relatively high molecular weight polyol. These prepolymers thus have an excess of isocyanate, or “free” isocyanate groups, which react with atmospheric moisture to improve the finished properties of the reactive hot melt adhesive. In certain embodiments the amount of free isocyant is about 1-5 percent by weight.

In certain embodiments the polyols, isocyanates, and/or prepolymers comprising the primary components of the reactive hot melt adhesive are formulated such that the viscosity of the adhesive formulation is sufficiently low at the application temperature to enable efficient application to the substrate. The reactive hot melt viscosity increases as it cools to rapidly provide good adhesive properties.

In certain embodiments, the reactive hot melt polyurethane adhesive mixture forms a final, cured polyurethane adhesive with the following composition:

-   -   5-40 parts by weight of one or more isocyanate components or         pre-polymers based on isocyanate components as described above         and in the specific embodiments and examples herein;     -   60-95 parts by weight of a polyol component or a polyol-based         pre-polymer component, wherein the polyol component comprises         from about 5 weight percent to 100 weight percent of one or more         of the aliphatic polycarbonate polyols described above and in         the specific embodiments and examples herein;     -   0 to 1 parts by weight of one or more catalysts as described         above and in the specific embodiments and examples herein;     -   0 to 20 parts by weight of one or more chain extenders, wherein         the chain extenders molecules are substantially as described         above and in the specific embodiments and examples herein; and     -   0 to 10 parts by weight of one or more additives, wherein the         additives are selected from the group consisting of: fillers,         clays, blocking agents, stabilizers, thixotropic materials,         plasticizers, compatibilizers, colorants, UV stabilizers or         flame retardents as described above and in the specific         embodiments and examples herein.

D. Non-Reactive Solvent-Borne Polyurethane Adhesive

In another aspect, the present invention encompasses non-reactive solvent-borne adhesives. In certain embodiments, such solvent-borne adhesives compositions are derived from one or more of the aliphatic polycarbonate polyol compositions as defined above and in the embodiments and examples herein.

In certain embodiments the solvent-borne adhesives are produced by reacting one or more aliphatic polycarbonate polyols with one or more isocyanates and possibly with one or more additional polyols and/or all other additives described above to create higher molecular weight prepolymers and/or polyurethane adhesives. These high molecular weight polyurethanes are then dissolved in one or more solvents for application onto various substrates. In these embodiments the solvent-borne adhesive is described as a one-component system. Additional fillers and performance enhancing additives may be included in the formulation.

In certain embodiments, solvent-borne cross-linkers are added to solvent-born polyurethane adhesives as described above to improve the strength and resistance of the finished adhesive. The crosslinkers may be any combination of aliphatic polycarbonate polyols, additional polyols, and isocyanates described above and may also be other types of thermosetting components. In these embodiments the solvent-borne adhesive is described as a two-component reactive system and are thus similar and/or equivalent to the two-component reactive adhesives described above, in the embodiments in which these systems are dissolved in one or more solvents.

In certain embodiments, the non-reactive solvent-borne adhesive mixture forms a final, cured polyurethane adhesive with the following composition:

-   -   5-30 parts by weight of one or more isocyanate components or         pre-polymers based on isocyanate components as described above         and in the specific embodiments and examples herein;     -   70-95 parts by weight of a polyol component or a polyol-based         pre-polymer component, wherein the polyol component comprises         from about 5 weight percent to 100 weight percent of one or more         of the aliphatic polycarbonate polyols described above and in         the specific embodiments and examples herein;     -   0 to 1 parts by weight of one or more catalysts as described         above and in the specific embodiments and examples herein;     -   0 to 20 parts by weight of one or more chain extenders, wherein         the chain extenders molecules are substantially as described         above and in the specific embodiments and examples herein; and     -   0 to 10 parts by weight of one or more additives, wherein the         additives are selected from the group consisting of: fillers,         clays, blocking agents, stabilizers, thixotropic materials,         plasticizers, compatibilizers, colorants, UV stabilizers or         flame retardents as described above and in the specific         embodiments and examples herein.

E. Non-Reactive Water-Borne Adhesive

In one aspect, the present invention encompasses reactive water-borne adhesives. In certain embodiments, such water-borne adhesives compositions are derived from a mixture containing one or more of the aliphatic polycarbonate polyol compositions as defined above and in the embodiments and examples herein.

In certain embodiments the water-borne adhesives are produced by reacting one or more aliphatic polycarbonate polyols with one or more isocyanates and possibly with one or more additional polyols and/or all other additives described above to create higher molecular weight prepolymers and/or polyurethane adhesives, which are then dispersed in water and known as polyurethane dispersions (PUDs). In certain embodiments, they may contain low levels of solvents to help stabilize the polymers in water.

In certain embodiments, the solids content of the final PUD adhesive is in the range of 25-75%, preferably in the range of 35-50%. In certain embodiments, the water-borne adhesives are formulated to be on the very high or low end of these ranges depending on viscosity requirements, other processing considerations, and finished adhesive properties required.

In certain embodiments, water-borne cross-linkers are added to water-born PUDs as described above to improve the performance of the finished adhesive. The crosslinkers may be any combination of aliphatic polycarbonate polyols, additional polyols, and isocyanates described above and may also be other types of thermosetting components. In these embodiments the water-borne adhesive is akin to the two-component reactive system described above (except it is dispersed in an aqueous system) in the embodiments in which these systems are dispersed or emulsified in water.

In certain embodiments, the non-reactive water-borne adhesive mixture forms a final, cured polyurethane adhesive with the following composition:

-   -   20-50 parts by weight of one or more isocyanate components or         pre-polymers based on isocyanate components as described above         and in the specific embodiments and examples herein;     -   50-80 parts by weight of a polyol component or a polyol-based         pre-polymer component, wherein the polyol component comprises         from about 5 weight percent to 100 weight percent of one or more         of the aliphatic polycarbonate polyols described above and in         the specific embodiments and examples herein;     -   0 to 1 parts by weight of one or more catalysts as described         above and in the specific embodiments and examples herein;     -   0 to 20 parts by weight of one or more chain extenders, wherein         the chain extenders molecules are substantially as described         above and in the specific embodiments and examples herein; and     -   0 to 10 parts by weight of one or more additives, wherein the         additives are selected from the group consisting of: fillers,         clays, blocking agents, stabilizers, thixotropic materials,         plasticizers, compatibilizers, colorants, UV stabilizers or         flame retardents as described above and in the specific         embodiments and examples herein.

F. Non-Reactive Hot Melt Adhesives

In one aspect, the present invention encompasses non-reactive hot melt adhesives. In certain embodiments, such non-reactive hot melt adhesives compositions are derived from a mixture containing one or more of the aliphatic polycarbonate polyol compositions as defined above and in the embodiments and examples herein.

In certain embodiments the non-reactive hot melt adhesives are produced by reacting one or more aliphatic polycarbonate polyols with one or more isocyanates and possibly with one or more additional polyols and/or all other additives described above to create higher molecular weight polymers and/or polyurethane adhesives. Additional fillers and performance enhancing additives may be included in the formulation.

In certain embodiments the polyols, isocyanates, prepolymers and/or polyurethane adhesives comprising the primary components of the non-reactive hot melt adhesive are formulated such that the viscosity of the adhesive formulation is sufficiently low at the application temperature to enable efficient application to the substrate. The non-reactive hot melt viscosity increases as it cools to rapidly provide good adhesive properties. In certain applications, they are formulated to have melt viscosities between 25,000 and 500,000 mPa*s, more preferable between 50,000 to 250,000 mPa*s.

In certain embodiments, the non-reactive hot-melt adhesive mixture forms a final, cured polyurethane adhesive with the following composition:

-   -   1-80 parts by weight of one or more isocyanate components or         pre-polymers based on isocyanate components as described above         and in the specific embodiments and examples herein;     -   20-99 parts by weight of a polyol component or a polyol-based         pre-polymer component, wherein the polyol component comprises         from about 5 weight percent to 100 weight percent of one or more         of the aliphatic polycarbonate polyols described above and in         the specific embodiments and examples herein;     -   0 to 1 parts by weight of one or more catalysts as described         above and in the specific embodiments and examples herein;     -   0 to 20 parts by weight of one or more chain extenders, wherein         the chain extenders molecules are substantially as described         above and in the specific embodiments and examples herein; and     -   0 to 10 parts by weight of one or more additives, wherein the         additives are selected from the group consisting of: fillers,         clays, blocking agents, stabilizers, thixotropic materials,         plasticizers, compatibilizers, colorants, UV stabilizers or         flame retardents as described above and in the specific         embodiments and examples herein.

G. Hybrid Systems

In certain embodiments, any of the above reactive and non-reactive adhesive formulations are combined with other adhesive chemistries in hybrid systems. In certain embodiments, the finished adhesives are urethane acrylic systems which can take a number of forms, including aqueous systems using water-dispersable isocyanates with PUDs and acrylic emulsion polymers, mixing acrylic and hydroxyl polyols to create co-polymerized resins, and the like. In certain embodiments, vinyl-terminated acrylic polymers are used to improve impact resistance. In certain embodiments, polyurethanes with acrylic functionality are also used in anaerobic or radiation-cured adhesives to increase toughness. In certain embodiments, urethanes are combined with epoxy chemistries using amine curing systems to create fast-curing adhesives for structural and heavy duty applications.

VI. EXAMPLES A. Example 1 One-Component Adhesive Formulation

In Example 1, a series of reactive one-component adhesives were formulated and a qualitative assessment of their performance was completed. In this example, a 620 Mw PPC diol with a measured OH # of 181 was formulated in a 1/2/1 equivalent ratio of polyol to isocyanate to chain extender to produce a prepolymer of ˜7.5% NCO. First, the required amount of 2,4/4,4-MDI was weighed into a 3 neck flask and heat to 80° C. The aliphatic polycarbonate polyol was heated up to 50° C. or slightly higher if the viscosity is too high to be easily pourable. The polyol was added to the isocyanate with stirring at such a rate that the reaction temperature is maintained at approximately 80° C. After all the polyol was added, heating continued with stirring for an additional 3 hours. The prepolymer was transferred to a bottle and seal under dry N₂. The prepolymer composition is shown below.

Novomer polyol 2,4-MDI 1/2/1 308 250

The percent NCO content was measured and compared to the theoretically calculated value and was shown to have good agreement. The prepolymers are then subject to lap shear testing (Lap Shear Strength of Adhesively Bonded Metal Specimens ASTM D1002). One inch wide cold rolled steel plates are marked at the ½″ mark. 10 g of prepolymer is readied and 0.1 g of glass spacer beads are added and mixed in. The mix are then spread on 1 of the metal strips within the ½″ by 1″ area and the second strip is overlapped ½″ to the first and then the two strips clamped together and left to cure at room temperature for 72 hour. Three samples are prepared for each prepolymer. After curing for 72 hour, the test specimens are clamped in the Instron and separated.

B. Example 2 Two-Component Adhesive Formulation

In Example 2, a series of reactive two-component adhesives were formulated and a qualitative assessment of their performance was completed. In this example, a 620 Mw PPC diol with a measured OH # of 181 was formulated in two different formulations, a 1/2/1 and a 1/3.5/1 equivalent ratio of polyol to isocyanate to chain extender to produce a ˜7% and a ˜14% NCO prepolymer, respectively. First, the required amount of 2,4/4,4-MDI was weighed into a 3 neck flask and heat to 80° C. The aliphatic polycarbonate polyol was heated up to 50° C. or slightly higher if the viscosity is too high to be easily pourable. The polyol was added to the isocyanate with stirring at such a rate that the reaction temperature is maintained at approximately 80° C. After all the polyol was added, heating continued with stirring for an additional 3 hours. The prepolymer was transferred to a bottle and seal under dry N₂. The prepolymer composition is shown below.

Novomer polyol 2,4-MDI 1/2/1 308 250 1/3.5/1 308 437.5

The percent NCO content was measured and compared to the theoretically calculated value and was shown to have good agreement.

% NCO of the Prepolymers 1 eq Polyol/3.5 eq MDI Measured % NCO Polyol Theoretical % NCO 1 2 Ave Poly G 20-181 14.05 12.63 12.56 12.60 PTMEG 650 13.74 13.48 13.42 13.45 CAPA 2067A 13.81 13.84 13.78 13.81 Novomer 14.09 13.70 13.64 13.67

The prepolymers are then subject to lap shear testing (Lap Shear Strength of Adhesively Bonded Metal Specimens ASTM D1002). One inch wide cold rolled steel plates are marked at the ½″ mark. 10 g of prepolymer and the equivalent amount of butanediol are mixed together, then 0.1 g of glass spacer beads are added and mixed and lastly 1 drop of tin catalyst (T-9) was added and mixed in. The mix are then spread on 1 of the metal strips within the ½″ by 1″ area and the second strip is overlapped ½″ to the first and then the two strips clamped together and left to cure at room temperature for 72 hours. Three samples are prepared for each prepolymer. After curing for 72 hour, the test specimens are clamped in the Instron and separated.

C. Example 3 Two Component PPC-Based Adhesive Formulation Compared to a Commercially Available Polyol-Based Adhesive Formulations

In this example, the objective was to determine performance of CO₂-based poly(propylene-carbonate) diol (PPC diol) Novomer 58-076 in polyurethane adhesives. A two-component adhesive was formulated with Novomer 58-076 polyol, 1,4-BD as a chain extender, and 4,4′-MDI isocyanate at MDI/Polyol/Chain extender equivalent ratio 2.02/1/1. As reference, two component polyurethane adhesives were formulated using Eternacoll UH-50 polycarbonate polyol, 1, 4-BD chain extender and 4,4′-MDI isocyanate and using Fomrez 44-160 polyester polyol, 1, 4-BD chain extender and 4,4′-MDI isocyanate. All polyurethane systems were formulated at the same hard segment concentration.

The polyol and chain extender (previously degassed) were preheated at 70° C., weighed into Speed Mixer cup, benzoyl chloride added and all components were mixed via Speed Mixer (FlackTek Inc.) for 60 seconds at 2200 rpm (Component B). The mixture was conditioned for additional 15 minutes at 70° C.

Required amount of melted MDI was placed into a syringe and conditioned at 70° C. (Component A).

Metal plates were conditioned at 120° C. Component A was added to Component B and all components mixed via Speed Mixer for 20 seconds at 2200 rpm Immediately after mixing, about 0.075 g of the resin was placed in the center of overlapping area of each plate. Before gel time, two plates were joined via over-lapping area, closed with clamps and left to cure for 2 hours at 120° C. followed by 20 hours at 110° C. The samples were left to age at room conditions for 5 days prior to testing.

Two-component polyurethane adhesive was composed of Component A which was straight isocyanate 4,4′-MDI and Component B which was mixture of polyol, chain extender, and small amount of benzoyl chloride. The gel time of Eternacoll UH-50-based system was too fast to handle in preparation of adhesive samples. Benzoyl chloride was added in small amount to slightly increase the gel time.

Two component polyurethane systems based on NCO— prepolymer was also too fast (gel time 60 seconds) and was not practical for laboratory preparation of adhesive samples, as well.

Both types of polyurethane adhesive, based on Novomer 58-076 polyol and Eternacoll UH-50 exhibited similar stress-strain properties, with yields at low strains (about 2% strain). The adhesion properties at room temperature were also close. However, adhesives based on Novomer 58-076 unexpectedly exhibited much better retention of adhesion strength at 70° C. as compared to adhesive made with Eternacoll UH-50. The retention of stress at yield at 70° C. of Novomer 58-076 adhesives was 61% as compared to 29% of Eternacol UH-50 adhesive. The strain at yield for Novamer 58-076 adhesive at 70° C. increased slightly as compared to room temperature. The strain at yield decreased for Eternacol UH-50 polyol based adhesive. In addition, Novomer polyols performed favorably in a number of additional performance areas including solvent resistance, clarity, and adhesion to a range of substrates—these results are summarized in FIGS. 1-7.

By blending Novomer PPC with polyester polyols over a range of 20-58% (using formulations similar to those described above for the pure materials), a range of soft and hard adhesives were prepared. A summary of the properties of these formulations are shown in FIG. 8.

TABLE 2 Formulation and properties of two-component polyurethane adhesives based on polycarbonate polyol Novomer 58-076 UH-50 (50% HS) (50% HS) Type of Adhesive Formulation (pbw) Component B Novomer 58-076 14.025 13 1,4 Butane Diol 2.052 2.381 Benzoyl chloride 3 drops 3 drops Component A Mondur M 11.949 11.522 Hard segment, % 50 50 Adhesive sample preparation Components temp., ° C. 70 70 Gel Time 3-4 minutes 100 s Curing time and temperature  2 hours at 120° C.  2 hours at 120° C. Postcuring time and temperature 20 hours at 110° C. 20 hours at 110° C. Retention of Retention of properties properties (70° C./RT) % (70° C./RT) % Adhesive properties, RT Load at Failure, N/mm² 1850 ± 266 1166 ± 156 Tensile Energy to Break, in-lbf/in³ 27 ± 4 17 ± 2 Modulus, psi 188948 ± 19184 181099 ± 31962 Stress at Yield, psi 3542 ± 164 3566 ± 120 Strain at Yield, %  2.19 ± 0.16  2.10 ± 0.17 Adhesive properties, 70° C. Load at Failure, 70° C., N/mm² 586 ± 62 32 251 ± 17 21 Tensile Energy to Break, 70° C., in-lbf/in³  3.03 ± 0.76 11  0.431 ± 0.068 2.5 Modulus, 70° C., psi 117612 ± 22535 62 128160 ± 17070 71 Stress at Yield, 70° C., psi 2174 ± 109 61 1039 ± 89  29 Strain at Yield, 70° C., %  2.75 ± 0.54 125  1.02 ± 0.15 50

D. Example 4 Hot Melt Adhesive

In this example, a series of non-reactive hot melt adhesives were formulated and a qualitative assessment of their performance was completed.

A 620 Mw PPC diol was reacted at 120% theoretical with MM103 isocyanate and labeled HM #1. It was hard at RT but after more curing it was applied to bond two stirring sticks. It was still har at RT, but it was appropriately gummy for a hot melt adhesive at 250F. Likewise, a higher 3000 Mw PPC diol was reacted with MM103 at 120% theory, called HM #2. It was applied to two stirring sticks, and this formulation, and the bonded wooden sticks were left in the oven overnight at 200F.

The HM #1 stick bonded samples were evaluated on. The 620 Mw PPC created a strong bond, moreover, where it had only coated one stick, the cured adhesive was extremely durable to screwdriver scraping. The composition also adhered strongly to the wood of the stick.

The HM#2 stick was tough and strong at RT. The bonded sticks had a very good bond at room temperature. 

1-97. (canceled)
 98. An isocyanate-terminated prepolymer comprising segments derived from one or more aliphatic polycarbonate polyols derived from the copolymerization of carbon dioxide and one or more epoxides and having a primary repeating unit with a structure:

where R¹, R², R³, and R⁴ are, at each occurrence in the polymer chain, independently selected from the group consisting of —H, fluorine, an optionally substituted C₁₋₄₀ aliphatic group, an optionally substituted C₁₋₂₀ heteroaliphatic group, and an optionally substituted aryl group, where any two or more of R¹, R², R³, and R⁴ may optionally be taken together with intervening atoms to form one or more optionally substituted rings optionally containing one or more heteroatoms.
 99. The isocyanate-terminated prepolymer of claim 98, wherein the aliphatic polycarbonate polyol is characterized in that at least 99%, at least 99.5%, at least 99.7%, or at least 99.8% of the end groups are —OH groups.
 100. The isocyanate-terminated prepolymer of claim 98, wherein the aliphatic polycarbonate polyol comprises a copolymer of carbon dioxide and ethylene oxide.
 101. The isocyanate-terminated prepolymer of claim 98, wherein the aliphatic polycarbonate polyol comprises a copolymer of carbon dioxide and propylene oxide.
 102. The isocyanate-terminated prepolymer of claim 98, wherein the aliphatic polycarbonate polyol comprises a terpolymer of carbon dioxide and ethylene oxide along with one or more additional epoxides selected from the group consisting of propylene oxide, 1,2-butene oxide, 2,3-butene oxide, cyclohexene oxide, 3-vinyl cyclohexene oxide, epichlorohydrin, glicydyl esters, glycidyl ethers, styrene oxides, and epoxides of higher alpha olefins.
 103. The isocyanate-terminated prepolymer of claim 98, wherein the aliphatic polycarbonate polyol comprises a terpolymer of carbon dioxide and propylene oxide along with one or more additional epoxides selected from the group consisting of ethylene oxide, 1,2-butene oxide, 2,3-butene oxide, cyclohexene oxide, 3-vinyl cyclohexene oxide, epichlorohydrin, glicydyl esters, glycidyl ethers, styrene oxides, and epoxides of higher alpha olefins.
 104. The isocyanate-terminated prepolymer of claim 98, wherein the aliphatic polycarbonate polyol has a number average molecular weight (M_(n)) in the range of about 500 g/mol to about 10,000 g/mol, or between about 500 g/mol and about 5,000 g/mol, or between about 500 g/mol and about 4,000 g/mol, or between about 500 g/mol and about 3,000 g/mol, or between about 500 g/mol and about 2,500 g/mol, or between about 500 g/mol and about 1,500 g/mol.
 105. The isocyanate-terminated prepolymer of claim 98, wherein the aliphatic polycarbonate polyol is characterized in that, on average in the polyol, the percentage of carbonate linkages is 95% or greater or is 99% or greater.
 106. The isocyanate-terminated prepolymer of claim 98, wherein the aliphatic polycarbonate polyol is characterized in that, on average in the polyol, the percentage of carbonate linkages is 99% or greater.
 107. The isocyanate-terminated prepolymer of claim 98, having the following structure:

wherein black rectangles

represent the carbon skeleton of the diisocyanate reacted with the aliphatic polycarbonate polyol to produce the isocyanate-terminated prepolymer; Q is 0 or an integer between 1 and about 50; n is at each occurrence, independently an integer from about 3 to about 1,000; and

is a multivalent moiety.
 108. The isocyanate-terminated prepolymer of claim 107, wherein

is derived from a polyfunctional chain transfer agent having a formula:


109. The isocyanate-terminated prepolymer of claim 108, wherein

is derived from a dihydric alcohol.
 110. The isocyanate-terminated prepolymer of claim 108, wherein y is 0 and x is greater than
 2. 111. The isocyanate-terminated prepolymer of claim 98, further comprising one or more additional polyols selected from the group consisting of polyether polyols, polyester polyols, and mixtures of these.
 112. The isocyanate-terminated prepolymer of claim 98, wherein the aliphatic polycarbonate polyol is selected from the group consisting of:

wherein, t is an integer from 1 to 12 inclusive, and R^(t) is independently at each occurrence —H, or —CH₃.
 113. The isocyanate-terminated prepolymer of claim 98, comprising urethane linkages derived from aliphatic polyisocyanates.
 114. The isocyanate-terminated prepolymer of claim 113 wherein the aliphatic isocyanate is selected from the group consisting of: 1,6-hexamethylene diisocyanate (HDI), 1-isocyanato-3-isocyanatomethyl-3,5,5-trimethyl-cyclohexane (isophorone diisocyanate, IPDI), and 4,4′-diisocyanato dicyclohexylmethane, (H₁₂MDI or hydrogenated MDI).
 115. The isocyanate-terminated prepolymer of claim 98, comprising urethane linkages derived from aromatic polyisocyanates.
 116. The isocyanate-terminated prepolymer of claim 115 wherein the aromatic diisocyanate is selected from the group consisting of: toluene diisocyanate (TDI) and methylene diphenyl diisocyanate (MDI).
 117. An isocyanate-terminated prepolymer having the formula:

where

is derived from a dihydric alcohol; and n is an integer from 2 to about
 50. 118. The isocyanate-terminated prepolymer of claim 117 wherein the dihydric alcohol from which

is derived is selected from the group consisting of: 1,2-ethanediol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 2,2-dimethylpropane-1,3-diol, 2-butyl-2-ethylpropane-1,3-diol, 2-methyl-2,4-pentane diol, 2-ethyl-1,3-hexane diol, 2-methyl-1,3-propane diol, 1,5-hexanediol, 1,6-hexanediol, 1,8-octanediol, 1,10-decanediol, 1,12-dodecanediol, 2,2,4,4-tetramethylcyclobutane-1,3-diol, 1,3-cyclopentanediol, 1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, 1,4-cyclohexanediethanol, isosorbide, glycerol monoesters, glycerol monoethers, trimethylolpropane monoesters, trimethylolpropane monoethers, pentaerythritol diesters, pentaerythritol diethers, and alkoxylated derivatives of any of these.
 119. The isocyanate-terminated prepolymer of claim 117 wherein the dihydric alcohol from which

is derived is selected from the group consisting of: diethylene glycol, triethylene glycol, tetraethylene glycol, higher poly(ethylene glycol), such as those having number average molecular weights of from 220 to about 2000 g/mol, dipropylene glycol, tripropylene glycol, and higher poly(propylene glycol) such as those having number average molecular weights of from 234 to about 2000 g/mol.
 120. An isocyanate-terminated prepolymer having the formula:

where

is derived from a dihydric alcohol; and n is an integer from 2 to about
 50. 121. (canceled)
 122. (canceled) 